I’ve been on the internet long enough to say it won’t. It will last a long time depending on the design of the system that creates the communities (mods, upvotes/downvotes, rules, algorithms, etc), but even that is limited because eventually every community reaches the size it needs to to encourage toxicity, echo chambers, circlejerks, and attracting even more toxic people from outside the communities.

It took reddit many years to start reaching that point though, I hope it takes these federated sites longer. And hopefully due to their design, they can keep most of the toxic people isolated.