They may be thinking that you were suggesting a tool that would allow multiple accounts on a server (which would promote sock-puppeting). I assume that when you said “account” you meant “server” (with a single account).
Chrome for personal use, Brave for work. I used to use Firefox but I need tab groups and I’d prefer a native solution for that. Simple Tab Groups seems unstable.
That depends on what the sever runs. For my NAS, sure, Debian is fine. But I don’t expect it to run anything that bleeding edge, and if I do there are often containers.
However, two years ago I tried to bring up a new headless NUC as a Plex server with Debian (because that’s what I’ve been using for the last 20 years) but had to give it up because of all the hoops you have (had?) to jump through to get it working with Quicksync in Debian. With Ubuntu it just worked.