If I have a friend that likes Gears and Halo and therefore buys an X1, and I like God of War, Uncharted, Horizon Zero Dawn, and Japanese games and therefore buy a PS4...

We would be able to play multiplatform online games together without wither of us having to buy an extra console.

I think the difference is pretty clear.

Doom 2016 and now Wolfenstein 2 suggest otherwise. These two are among other games that indicate power alone isn't the biggest factor when it comes to porting.

Additionally, the PS4 and X1 are very close in terms of power and yet there are multiplats released on the former but not the latter. Seems to me power isn't too dominant a factor.

Game streaming will kill it.

Well depends on the view you see it on. For a buisness perspective its good however from a consumers perspective its bad. PS lost 2% of there marketshare instantly for there Fortnite drama. If PS continues to stay out of the loop and allow there rivals to continue being user friendly than they will build a greedy reputation much like there PS3 era and start losing ground. PS connot take on Xbox and Nintendo by themselves especially with Xbox funding tons in there buisness model and Nintendo dishing out masterpieces every year. Sure PS will always have there place in the gaming industry with there own studios however its a online/digital future. Its time that the industry to start supporting eachother and continue to grow the market than trying to monopolize the market because of sales and the lead.

Here's an article that explains the MS marketing BS when it was market leader with the 360.

https://kotaku.com/5813740/i-saw-the-playstation-3-wired-to-play-against-an-xbox-360-but-you-wont

"As cool as this sneak peek was, Trion can't let the finished Xbox 360 game connect to the PS3. "Microsoft won't let Sony players play against them," Rodberg said, before suggesting we change the topic to something less sensitive. Presumably the barrier is a corporate and/or technical incompatibility between the Xbox 360's Xbox Live and Sony's PS3/PSP PlayStation Network. Those services are separate enough that people who play, say, Call of Duty on one, can't play that game against owners of the other, rival console."

"I checked with Microsoft to be sure Rodberg wasn't maybe just mis-hearing them. Maybe Microsoft wanted to break the barrier too? Here's a Microsoft spokesperson saying "no," while promoting how awesome the Xbox 360's online service is: "Xbox Live delivers the best entertainment experience unmatched by anyone else, with 35 million actively engaged members. We have a high level of expectation for our game developers to ensure that all Live experiences remain top notch. Because we can't guarantee this level of quality, or control the player experience on other consoles or gaming networks, we currently do not open our network to games that allow this cross-over capability."

So what happened to not being able to guarantee a Live level of quality and control on other console networks? Not as important when your no longer market leader?

Also something else to think about based on what Shawn Layden of PS said.

“We’re hearing the criticism,” said Layden. “We’re looking at a lot of the possibilities. You can imagine that the circumstances around crossplay and third-party accounts affect a lot more than just one game.”

I wouldn't be surprised if some third party devs/pubs don't really want cross play, even if they say they do, because for everyone who buys the console version of the game earlier, then buys another copy on PC later after being ported, or vice versa, is money they would probably lose out on in the future. Also for those hardcore or wealthy console gamers who will go out and buy two or three different platforms and the same game on all 2 or 3, so they can play with their friends who only have one platform each, is lost as well. PS is the last one standing in the way of cross play at the moment, and so it would in a way be up to them to help those third parties, or potentially piss them off by allowing it as market leader and pass the buck onto all of them instead, forcing them to cave as well or constantly be bombarded with negative PR.

No doubt the power of marketing and PR is being used to it's extreme with the whole cross play scenario from past to present.

I agree with the OP.
Sony has the userbase to thrive on their own without crossplay. They have nothing to gain businesswise by allowing it, it would only benefit the competition. I support them all the way. This is not a feels issue for me.
Is there any data on how many gamers there actually are on Xbox and Switch who would even need access to PS4 players in order to enjoy their multiplayer experience? I bet this issue is far more irrelevant than it's made out to be. Just whining on principle.
And if it is a problem for you, just get with the program and buy a PS4 already. You know you need it.

My comment was about why I should care about crossplay when shopping for a console, not what other people care about.  Someone else might get excited that the other person in a game might be playing on a different console but I honestly couldn't care less.

No offense, but I want real world numbers.  Hypotheticals are fine but I'm not going to base a decision off that.  What is the actual difference?  Does a PS4 player have to wait minutes more than an Xbox/Switch owner?  Seconds?  Is there any data about connection quality?  I want to know about the reality of the situation.  If this is going to be meaningful to me, I want tangible reasons.  This seems to be a big deal for you so I figured you'd have some hard data.

I understand exactly why developers want this but I'm looking for an interview or article where they explain meaningful positives for players.

It's kind of funny but the only really good reason I've read was back when Xbox wasn't allowing crossplay and they lost out on games that came to Playstation instead.  The PS4 user base kind of negates that in this situation, though, at least as far as I know, but that is a potentially meaningful negative.

I don't particularly care about cross play either. It can actually be a bad thing. Pc users have an advantage over consoles because of keyboard and mouse. Ps4 and xbox one have an advantage over switch because of things like framerates and draw distances, albeit a small one. Switch has the edge over mobile players.

Sony really stuffed up with the account locking though on fortnite. That is very anti consumer.

I didn't know. Learn something new every day. I'll have to test it. I haven't had PS+ in a year. Maybe more. Plus Fortnight isn't my type of game. I just assumed that, if you play online, you pay for the online service. I even expect the Switch to be the same way.

You might know someone you'd like to play with and with crossplay, hardware compatibility will be much less of an issue.

No offense taken. I understand your need for numbers and data but as far as I know, this sort of information isn't readily available thus I can only offer a rationalist approach.

If you find objection to previous reasoning provided, please don't hesitate to post your objection.