Low end machines
On the point about low end machines, I've just been messing about with an old Intel Atom 330 board with 2GB of RAM and a 120GB SSD. I tried Linux Mint 20, MX Linux 19, Windows 8 and Windows 10 2004. Of those four, Windows 8 was surprisingly good, MX Linux was pretty usable, while Mint 20 and Windows 10 were both dog slow.
I'm not suggesting Mint 20 or Windows 10 are slow on sensible hardware, but they must have evolved in a way that expects a certain level of CPU power and/or RAM to be available. Lots of parallel tasks perhaps.
My biggest surprise with Linux is how much better the more lightweight window managers now look. Years ago I'd look at screenshots of anything that wasn't Gnome or KDE and turn away in horror. Now, something like xfce looks good to my eye.
Back to Mint 20 - personally I feel that although it still doesn't look quite as polished or modern as Windows or macOS, I'd happily trade that to get away from things like the Catalina security model in the Mac world. In the Windows world there's even more I want to get away from - Windows 10 increasingly feels like a stack of workarounds on top of other workarounds. The UI looks tired and I'm sick of seeing teasers about how it might look if they get their arses into gear. And in general, they are pushing things I don't want - it's now very difficult to sign in with a local account for example. You have to kill the network at setup time, it's just ridiculous.