I don't know anyone who goes through the trouble to spoof their user agent and I know plenty Linux users.
Tons of people did and do this to get higher resolution on a certain streaming site.
The archwiki Firefox privacy guide comes to mind, which mentions UA spoofing:
https://wiki.archlinux.org/title/Firefox/Privacy
I do, to access YouTube TV on my Ubuntu HTPC.
Tons of people did and do this to get higher resolution on a certain streaming site.