To be honest, I was very excited for Civ7 up until they revealed the mechanics in detail, then I was wary, and then as more info came out, I became more wary, then as it released in a sorry state, it has cut my excitement for sure. So now that the game is out, the reviews are bad, and people are unlikely to want to invest - I use myself as an example.
For the people who bit the bullet and bought it anyway or preordered, they're most likely going to be the most upset in the forums. Even the people who liked the new mechanics in concept still didn't enjoy the game due to the lack of polish. I would presume only a small minority is happy 'as-is'.
We'll see how this experiment pans out as the years go by, but this isn't the first time I've seen things go south on new releases, especially in this genre (AoE4 for example).
The best thing they could do after Civ7 would be a 'Civ Ultimate' - I think people would probably really enjoy a 'Greatest Hits' of Civilisation mechanics, that's something that would build consumer confidence and have people willing to invest. Especially after a game that has sort of dampened consumer confidence.
However, the sceptic in me thinks that while this game would be a hit financially in the short-term, it will suck for long-term success because - how on earth do you follow it up? (Similar situation to Smash Ultimate for example.)