I also went to local restaurants, they were extremely cheap but way too basic IMHO(However I think there was a special kind of a restaurant that is intended to be fancy but also for the locals. I was having a proper fish meal and a beer for about equivalent of 5$ in CUP at one of those). However I was told that I can't take any other bus than Viazul(the fancy tourist buses) for travelling between cities. Not that I would want to travel in one of those anyway, definitely not comfortable or safe to travel.
Here is one of the buses that the regular Cubans were traveling: https://imgur.com/a/jIynZMZ
For some reason, communists suck at automobile making.
OH! By the way, apparently CUC was discontinued a year ago in 1st of January 2021.[0]