Older than 30 nope, tech enthusiast yes, Linux user sort of, because my self-hosting servers run Linux but my personal daily driver is Windows. Windows native art programs have a lot of responsiveness problems and other random issues when running on Linux, and it's annoying to have to boot up a separate OS to use specific programs.
Taking the extremely tech-unsavvy fanartist community as a reference, it's not that federation and choosing a server is that difficult, that's just a lame excuse. Their usual social media platforms do UI redesigns, A/B testing and introduce weird limitations all the time. They just learn to cope with it.
People who don't care about tech don't think about the websites they use at all. In their minds, websites are just omnipresent things that exist naturally, like the sun. They only care about whether the website is able to connect them to their friends and showcase their posts to other people. They will only pay attention to the website if it introduces a change that affects their daily usage of it negatively, just like how people don't consciously think about the sun unless it inconveniences them.