People forget how poorly V was launched at release. Even VI...
V was brutal at launch. But thankfully the launch was before some of the modern online culture, and the parts it was brutal in were less integral to the core game. I think the "anger" over 1upt is less than the anger over ages/civ switching.
I mean, I remember being at a place where I got a new computer just as civ 5 was coming out (sort of joking that I bought the new computer for the game), but it was so absolutely dreadful at launch that I just quit and couldn't play it for a solid 6 months or more after launch because it was just so imbalanced, so broken, so terrible. Eventually I did give it another try, and while I never really loved it, I didn't necessarily hate it, but I just stopped playing it after a while and never really went back to pick it up. 700 hours in 5, 2600 hours in 6, 250 hours in 7 for me.
But all in all, I do think this launch will be more polarizing for them, I don't think we'll see the 9 year dev cycle before the next major version like we did for civ 6, if they can't bring people back in. My main hopes at this point:
1. nothing has been too bad in the dev cycle that there are permanent repercussions at FX. There are some games where a bad release could literally cause the studio to fold, or the publisher to break off and not want to put in more.
2. They will find something way to effectively get in a form of a classic mode that is enough to appease some people, while not fully taking a 180 from the initial ages and switching
3. We'll get enough DLC/expansions to have a relatively complete geographic/timeline roster
I think there's enough that they can hopefully bring it back. Maybe it will be time to switch the creative lead on the game for expansions and take a few pieces in another direction. If they can't turn it around commercially, then the questions would become how early they move development focus onto the next version, and what direction they take that.