For my workplace it was a choice of downloading duo on the phone or getting sms codes. In the past year they cut out the sms codes, now you get a temporary code from the duo app you need to enter into the login portal vs just a push to duo.
There are TOTP apps for regular computer. I am using an old tablet for the microsoft authenticator and banking apps.
Technically it is pretty much like a phone but it is not used as a phone. No number, no sim card.
I am pretty sure some of these apps could work on waydroid too if needed.
So in the end all this discussion really depends if we are talking about the mobile device as a whole that you carry with you nearly all the time or some parts of the ecosystem that you may have at home.