I don't think any of those are really comparable, specifically not to the Scorpio. Looking at history we can't ignore that the transition to PS4/X1 saw 2 years worth of cross platform games, that in itself is a new normal. How many GBA games were released alongside a GB Color version. How many PS2 games were released alongside a PS3 version, day and date?

There were at least 46 titles released on both sixth- and seventh-gen platforms by the end of 2007. The PS2 was still getting at least a couple cross-gen games long after that, though to be fair those were all sports games (FIFA 14 had the distinction of being released across three generations, though I imagine the PS2 version was different from the PS4 version in ways besides visuals). Not counting indies and other small titles tailored for digital distribution, there were maybe 80 games released for both 7th- and 8th-gen systems. ~80 a lot more than 46, but not so much as to elicit surprise. It's also worth pointing out that third parties were not putting out many cross-gen games because they were still putting most of their efforts into developing for sixth-gen systems (esp. the PS2). The 360 did not have nearly the support in its first year as the PS4 & XBO did. The PS3 wasn't even out yet, and third parties had very small user base to work with. The PS2 was still outselling the 360 at the time. Also, the hardware differences were more profound. The 360's GPU was at least 38 times more powerful than the PS2's, while the XBO is only about 5.4 times more powerful than the 360, and the PS4's 7.6-7.7 times more powerful. Porting across generations was likely easier.

Taking everything into consideration, cross-gen support during the most recent transition was not especially unusual or noteworthy.

In the case of the Scorpio, the 4x difference in power is far more dramatic a change then any of the incremimental hardware updates Shadow1980  referenced. Practically speaking how much more powerful is the X2 going to have to justify excluiding Scorpio hardware support? Prior generations have typically been seperated by a factor of 8x or more.Even if we cut that in half, I don't see Microsoft bring out a 24TFLOP system at the turn of the decade at a $399 price point.

The 4x increase in power (or 2.4x in the case of the Neo) is going to 4K resolutions and VR. If you overlook all the ancillary PR BS about supposedly redefining generations, it's clear that 4KTV and virtual reality are the reason we're getting a mid-gen spec upgrade. It's perhaps no surprise that the last time a home system got a mid-gen spec upgrade was during the time when CD-ROM was starting to get big. If 4K wasn't introduced and made commonplace when it did, and if VR didn't suddenly become relevant again long after the initial early 90s hype fizzled out, then the Neo and Scorpio likely would not exist.

People are seeing alien pyramids when all they're really looking at is an ordinary rock. There is nothing new under the sun. There is no reason to assume that we're looking at a massive paradigm shift in the console industry.

Just like how the Playstation 4 cannot run all Playstation games like the old PS3 titles?

At-least on the PC, powerfull hardware can still run everything, even old titles... Many older PC's are still able to run new titles just fine, just with reduced quality.

I think your typical console will still have the same "life" length, there will just be more blurring of the hardware transitions by making more software forwards and backwards compatible, with more frequent hardware updates, which isn't a bad thing per-say.

With that said, I'll take a wait and see approach, I do like Microsoft's idea though if it means a more rapid advancement in technology whilst retaining a high level of compatability... I am tired of consoles holding back PC gaming and this would help fix that.