What are we going to do about it?
Do nothing, nothing about it. The great hordes of the unwashed have ruined every single place they've showed up starting in the early 90s. They don't want to be saved from the commercialization that has taken over the internet, to the contrary they thrive on it and are willing to put up with nearly anything to attract and keep it.
If most of Reddit shifted over to Lemmy it would get commercialized into a smoking crater. As soon as there's enough regular people using a thing the companies and venture capitalists will show up and at that point the game is over.
The best of the internet has always been built by and populated with people who don't fit into a box. It's that internet people keep trying to bring back but you can't hold the castle once it's being assaulted by the normies.
So the solution is to do nothing. Let the normies stay in their palaces of commercialization and corruption. It's for the best.