Well, that makes for a kind of big (rhetorical) question to ask yourself - is the tent about the game, or about the settings?
I think that's up to each fan to decide. For me, it's probably about the settings more than the game. There are much better RPGs out there I could be playing. I enjoy the plethora of lore associated with D&D at a level I don't actually enjoy rolling a d20 to hit and subtracting hit points to calculate damage. 5e is not even my favorite edition, I'd prefer to run my weekly game on AD&D 2e, I just respect my players' desire to play an edition that's still getting support from the publisher.
Maybe we should also have a clearer understanding of what constitutes or not a big tent, after all. People keep saying that "big tent doesn't mean it gets to be everything for everyone", but let's be honest: the idea of a 5e big tent was important as part of the playtest effort and lingered for a few years as a promise for the future. There was no warlord, but one would appear, eventually. There was no psionics, but we would get the system once they're ready to do Dark Sun. There was no tactical module, no epic play, no good rules for creating/selling/buying magic items, but... well, you got it.
Now, does 5e's tent gets to be called a big one just because a lot of people are playing it? Does it really support various playing/DMing styles? Is
Curse of Strahd a real horror take or just
Storm King's Thunder with vampires? If it's the first case, why it's authors couldn't spare a few words for the optional rules on fear/horror/corruption in the
Dungeon Master's Guide?
Funny enough, I'm not saying all that because 5e is not keeping me entertained
now. But we are 5.5 years into the edition and I cannot look at the last UA on psionics and not get worried. The message I got from it is: "Ok, at first they told you this ship would eventually sail some different waters, but now it's making too much money by always traveling the same route, and you should drop from it if you want to go somewhere else". Once more: that's a pity. I still see a lot of potential on the basic 5e engine. If WotC keeps failing to deliver the big tent, it's not because the core game cannot support it.
Another question to consider (that we don't have the data to answer, so we can only consider, not answer) - how many people will feel they are shoved out of the tent because their favorite setting of some decades past is not actively supported any more?
This, I guess we'll have to wait and see. I don't expect it to be an issue, because their tent is still growing to this date (Exandria/Ravnica fans, and all...), but I expect more people to drop the ship once they realize that actually developing the game beyond "look at this new storyline" and "look at this cleric that also deals +1d8 damage at 8th level" is not on their plans.
What I can say, for sure, is that I was not the only person in my gaming circle to get the wrong message from the last UA. Where we were not even considering PF2 two weeks ago, we're now being remembered that Paizo has at least shown some willingness to iterate and innovate upon their basic game in the past. That's more than you can say about WotC for more than five years now.
Also, sorry for the wall of text.