I'm trying to think of a non-system wars, non-toxic way to articulate this....
The biggest flaw of the Playstation 5 reveal (which showed lots of cool games)...
If you're telling me that not supporting the older console or not leaning into enhanced backwards compatibility will make you be able to produce true next gen experiences before the competition provides them, then you need to show me next gen game experiences...and give me release dates that are within a year of the console launch for those experiences. Realistically, I don't expect many huge jumps in the first 2 years for either console. It's not realistic. New experiences take time with the new tools. That's why I have no problem with Microsoft's cross-gen approach. Microsoft is selling the benefit of their cross gen approach as we'll get old games to feel newer as a result. Old games will get ray tracing and improved frame rates...which will feel like free Remasters. There will be some benefit and excitement to plug old games into the new system. Sony didn't show why their approach was going to have better results in the other direction. If old games won't feel new and often times won't even be ready, then will I be doing things in the Spider-man spin-off that I cannot see or do in the current PS4 version? Maybe that exists...but they didn't show it.
The evidence doesn't really support the narrative to abandon PS4 or be behind on backwards compatibility.