Personally the wifi version of wireless hotspot was always finicky for me on Linux, requiring a few restarts of the hotspot and the computer wifi to get synced up.

Wired tethering always worked instantly. Well, until now sadly :(. I tried to do this the other day and I just figured something was bugged, but I didn’t realise it is an iOS14 issue. Guess I am stuck with the wifi hotspot for now when I am out and about.