The NES didn't dominate because of gimmicks or fads, and neither did the PS1/2. The PS4 was indeed helped the by initial insanity of the Xbox One, but its sales are really nothing new.

When these kind of discussions come about im always reminded of the old saying (even though its proved to be inaccurate so dont try it out) :D

If you put a frog into boiling water, it will jump out. But if you put a frog into cold water, then slowly turn up the heat it will sit there and die.

What I mean by this, when the XBO and PS4 were being prepped for release Microsoft tried to force what they wanted onto the consumer. You need constant internet connection, cant trade games, almost like they were trying to push digital gaming onto you by removing the benefits of what buying the game physically gave you.

But I look now, and though they tried to force this sudden change oonto us and the consumer revolted, it feels this is where we are naturally heading now anyway. I myself and most people I know who own a PS4, and the consensus I get from what I see and read, alot of people have either moved to buying games digitally or have started heading that way. I never thought I would choose to buy games digitally over the discs, but now I rather buy a game on digital than on disc (the only exception being if there is a large difference in price between the two).

As we move that way, and continue to move that way - more people buying digitally, you need an internet connection and a pretty reliable one. By proxy any issues or disdain for the used games market goes with it, as you cant trade it. Even on smaller scale, more people who buy digitally means less who buy physical, meaning shops making money from selling games goes down, which (my own hypothesis) means to buy your used game from you they offer less for it (what you get offered for trading in games these days is sometimes insulting) because they dont want to pay anymore than is necessary when they have more stock of the game physically they find harder to move, and less people buying physical games over digital. All these things are driving down the desirability of owning your games on disc as opposed to digital.

I do believe we are slowly heading towards the model Microsoft envisioned back in 2013 when they unveiled XBO, only now we are in a pan that the heat is slowly being turned up, where as Microsoft wanted to drop us into the already boiling water.

Also reminds me of an analogy Armin Zola uses in Captain America the Winter Soldier when he is explaining Hydra's grand plan to Cap - OMG, Sony and Microsoft are Hydra!!! :O Well, Microsoft are Red Skull Hydra, and Sony are Alexander Pierce Hydra at least :D

P.S. Marvel reference for the win ^.^

DVD and Blu-ray isn't a 'fad'. The PS4 is selling well because it's the best console on the market with the most diverse library and new 1st party IPs. 

All consoles are fads. Some just take longer than others, like all fads.

Well that's news to me, considering all the other consoles that used CD formats that weren't nearly as successful. Having a CD format helps, sure. Considering that publishers found it to be a more cost effective and logical format choice over the archaic and expensive cartridge in comparison. Playstation was a perfect storm of fortunes and ideas that led to its success. Price, format, third-party relations, rival consoles being more cumbersome to develop for in comparison. And once the library was established, there was no stopping it.

Xbox was DVD based too and didn't nearly make a fraction of the PS2, and that had superior hardware. By that time, PS had become a trusted and established brand so that success had carried over regardless of format. Thing is, being an established brand will only take you so far when you introduce a 600 dollar console into the market. 

The PS4 is selling like this for all the same reasons that game hardware has sold like this before, Sony has just done very well with maximizing the strategic points this generation. I remember when Sony PR was an absolute disaster during the PS3 years. They seem to have learned a lot of lessons and are hitting the key issues instead. It is the games, it is the price, it is the multimedia functions, it is the timing. Riding off the vibrancy of the market this year in conjunction with the now robust PS4 library, they lowered the cost to an unignorable $200 ($150 at Gamestop) price point which dramatically increased demand for the console. Now when everyone who hasn’t gotten one wants one, they again dropped it to $249, just within grasp of those lingering consumers to nab it for Christmas. If they maintain that price or not, the after holiday season will still benefit from the heightened interest in the console, pushing this increased sales for a bit into 2018. It is possible Sony could ride these price cuts through 2018 but also possible that interest could taper off despite all efforts. 

This is dramatically different than past price cuts like the famous $99 Gamecube boost, because this time PS4 is a top choice console and has been all generation which has produced the best game library currently on the market. There is no “more in-demand higher tier console.” The price cut didn’t have to even happen for sales, but Sony did it anyway, to ensure a further increase in “demand” that would render Xbox One nearly obsolete, a bid to flatten the OneX launch and to keep Switch from completely taking the holiday. Everything worked out beautifully as planned. 

The reason why PS1 and PS2 did well was mostly because they didn't threat European gamers like second grade. The PS4 was superior to the Xone when hardware was concerned. MS shot itself with the DR'S and Sony simply kept momentum with third party deals and a steady flow of 1st party games. Especially from 2016 onwards.

I reeaaally don't think, good sir, that the PS1 only sold because it played CD's, and although the inclusion of DVD playback certainly helped the PS2 sales, it was, again, not the ONLY reason it sold. Not even close. So I have to take issue with you saying "we all know" that this is the case. I think most of us would say otherwise. There are many other factors contributing to what the sales of the PS1, PS2, and PS3 settled at. And yeah, the library of games was certainly a much bigger factor, and ties the success of all the PS consoles together much more closely than the playback of various media formats.

What you're calling fads aren't fads. Just new technology that at the time, we weren't sure of their longevity. CD, and to a far lesser extent DVD, are slowing in popularity but took decades to do so. That's not a fad, that's reliable and well received tech that succeeded at it's purpose. Mainstream consoles fully supported motion-controls since 2006 and they're still here and going strong nearly 12 years later. Touch screens have been here even longer than mainstream motion-controls, and pretty much dominate mobile gaming input methods thanks to modern cell-phones.

With that sad, the PS4 didn't bring us anything drastically new. It was largely a refinement of what was present last gen (more power, less waiting, improved main-controller, improved online experience, etc). So I get what you're saying. However, the same is true of it's main competition the X1. These two consoles launched around the same time and back then it was pretty clear which was better. At launch, the PS4 was more powerful, was cheaper (even if you wanted the camera which wasn't optional for X1), games installed faster, and at the time it seemed to have more exclusives on the way. The choice was obvious and SONY's just been able to hold onto that momentum.

"We all know PS1 and PS2 only sold because they played CD/DVD's"

How to lose all credibility with one sentence.