There seems to be a comparison of launch titles and saying ones that came a few months later aren't really launch games. That's fair enough.
But MS is talking years (closer to 2 than 1 is very possible) not weeks or months.
And let’s not confuse things. One thing is that we have to wait years to see a game using the hardware to the full. Other is to see a game using the hardware.
The extra CPU and SSD reading speed will be there day one. And it doesn’t take any magic for them to show their power.
New and improved physics models, new AI models, can be used just because up to 4 or more times the Jaguar compute power is availabe. Without having to explore the hardware a lot of doors will be available day one. Better world interaction, better animations, better everything can just be used because the compute power is there.
Associate this with the ssd speed that will also just be available day one, and you can create more complex worlds, or even travel in a faster way within them.
Remember the spider man speed demo Sony showed? How about a The Flash game in a city like that? It would never be possible on older hardware, but it will now be possible day one.
Creating compatibility with older consoles will deny access to all this. The CPU will only be used for extra fps, eventually a couple more NPCs, and that’s about it. There is just so much you can improve without changing the game mechanics core that allows you to say that you are playing the exact same game on all consoles.
The SSD will only allow faster level charges, bigger depth of view, and less clipping, but that is also about it.
If this console lasts 7 years, 2 years without using it’s hardware features in the way possible, is a lot. And if we believe a mid gen console is released, then the XsX is not worth the buy yet, specially for those who have an X or a PC.
For those with 1080p TVs, keeping the S for a couple years more may also be an option. The first party games will be there, and the thirds will probably not drop support either due to the larger user base.