Probably didn't even bother to diagnose the issue. It's hard to tell if it was even wayland related without logs and some digging. But lets just blindly blame wayland cause new thing bad!
Log in using wayland -> no desktop. Log in using x11 -> desktop. Clearly it's "wayland related" even if whatever root cause it is is something you wouldn't consider directly attributable to it. Logging into a graphical session is something that has just worked out of the box each other install on whatever random hardware I've used for many years. How is that classified as some nitpicky "new thing bad" complaint?
Well, it's like new car doesn't start but you have forgotten to put fuel into it, and now blame the car.
This is Linux desktop, like if you have never had a black screen before then I'm not sure what you expect. One culprit could actually be the home .config/.cache folders that have all kind of sh*t accumulated (like why do we still do it this way? It's horrible), so I usually rename them and try again to see if this is the problem behind the scenes.
Well, if I never had to put fuel into my old car then this would be a step back, no? I'm not a stranger to troubleshooting, and do a lot of it already, which occupies my energy and time for troubleshooting. I use Debian stable for a reason. It's mostly that if I didn't go looking for a new thing, it doesn't provide anything new that I want, it removes old things that I want, and it doesn't work without troubleshooting, why do I want this thing?
This specifically isn't the biggest issue for me right now because I use this machine mainly over ssh, but if I eventually can't do x-forwarding, RDP, or log in manually without finding some fix, that's a lot of extra work and lost functionality.