Running 20 year old binaries is not the primary use case and it is very manageable if you actually want to do that. I've been amazed at some completely ancient programs that I've been able to run, but I don't see any reason a 20 year old binary should "just work", that kind of support is a bit silly. Instead maybe we should encourage abandonware to not be abandonware? If you're not going to support your project, and that project is important to people, provide the source. I don't blame the Linux developers for that kind of thing at all.

devs are often being discouraged from compiling tools in a way that makes them work forever (since that makes the app bigger and potentially consume more memory)

This is simply not true. If you want your program to be a core part of a distribution, yes, you must follow that distribution's packaging and linking guidelines: I'm not sure what else a dev would expect. There is no requirement that your program be part of a distribution's core. Dynamic linking isn't some huge burden holding everyone back and I have absolutely no idea why anyone would pretend it is. If you want to static link go for it? There is literally nothing stopping you.

Linux desktop isn't actively working against disabled people, don't be obtuse. There is so much work being done for literally no money by volunteers and they are unable to prioritize accessibility. That's unfortunate but it's not some sort of hypocritical alienation. That also has likely very little to do with the Linux kernel ABI stability like you claimed earlier.

But this idea that "finally we have people that want Linux to work" is infuriating. Do you have any idea how much of an uphill battle it has been to just get WiFi working on Linux? That isn't because the volunteer community is lazy and doesn't want things to work: that's because literally every company is hostile to the open source community to the point of sometimes deliberately changing things just to screw us over. The entitlement in that statement is truly infuriating.