This dynamic is present in FB the website as well. You find clusters or groups of folks who re-amplify a point. It's so effective that you can find "Re-Open" rallies in your state driven by a shady "gun-rights" nonprofit. Even though polling largely supports the lock down and actions taken to curb the pandemic. You also find that outside the group people are a lot more nuanced and reasonable. It's fascinating. What is even more concerning is that a lot of bots drive this behavior.

I think the issue is that in the long term it dilutes FB. I know many people who don't post on FB, preferring Instagram etc... I know these are still FB platforms but it's a big shift. So FB will eventually become Usenet and effectively non-functional.

There's some type of social network that's between Instagram and FB that doesn't exist yet.