Don't big instances go against the purpose of the fediverse? (lemmy.world/ml)

I've been trying to make the switch, and it seems like most of the important communities are on lemmy.world and lemmy.ml

But then I also thought the main idea and benefict was that everyone has their communities, if one goes down you have the rest etc

But at this point, if lemmy.world messes up with X thing, it affects 90% of lemmy's users

So esentially, to me it seems like the trend will be main communities will keep growing if another reddit wave comes, and small communities of the same topic hosted on other instances will be as inactive, and the influx of people making big communities more active, will cause small communities to lose their few users because they wanna be on the active place

All the popular communities will be managed by the same moderators, and much like reddit, if you get banned in one, you'll get banned in all communities managed by said administrators. There has already been controversy with moderation in both of those instances but well

It is what it is, we can only wait and see