I honestly hate the idea of mid-gen consoles.
It's taking the PC model and supplanting that even more onto consoles.
The biggest benefit consoles have had has been the fixed hardware target for developers. It simplifies development and forces devs to maximize the use of the hardware, eeking out every last bit of performance and even leading to the development of new more efficient rendering technologies.
By providing mid-gen hardware upgrades (predicated solely on the sole benefit of providing higher resolutions/framerates), you complicate developers by providing multiple hardware targets, sucking up testing, iteration and optimisation hours, while also removing the impetus for devs to properly optimize their games or do R&D into developing new more efficient rendering methods, because why would they waste time on that when they can fob off the issue to gamers since they now have the option to upgrade their hardware.
And, it's not even as if I'm exaggerating or catastrophising here. The last-gen demonstrated this aptly, with many many devs no longer giving a shit about base consoles and releasing fucking awful, unoptimised base versions.
So you throw away part of what makes consoles so good for the privilege of being able to spend your hard-earned money on having to re-buy your console. It's dogshit.