Ubuntu just raised the minimum RAM requirement from 4gb to 6. While it might have been possible to run anything with a GUI on 4, I can't imagine that is a good experience.

When they turned Centos into streams, I cut my workstation over to Ubuntu. It has been a reasonable replacement. Only real issues were when dual booting Win10 horked my grub and snap being unable to sort itself on occasion. When they release 26 as an LTS, I'm planning to update. You are spot on - the desktop itself is reasonably lean. 100+ tabs in Firefox... less so. Mind you, the amount of RAM in the workstations I'm using could buy a used car these days.

I don't really get it. I have ran fleets of thousands of devices running Chrome in a container on Ubuntu server, and it's a nice experience. It took a lot to make it nice, but once it was there it was rock solid. This was with 1GB ram on a Pi 3. When we swapped to Pi4, we just had thousands on gigabytes of ram and thousands of cpu cores unused.

Does Firefox really not unload the tabs in that case?