Who defines "toxicity"? What you call toxicity others may call a good rebuttal, which to somebody sensitive to constructive criticism, may seem toxic, rude and offensive. So toxicity, like "hate speech", isn't a good standard because nobody can define a fair and useful standard.

Who defines "abuser". Same logic.

And an echo chamber is a place where one hears only friendly and supportive viewpoints. Has nothing to do with algorithms, unless the algorithm is designed to reinforce the echo chamber, which brings us full circle to my original comment.

Support free speech. Oppose any and all attempts to censor or restrict free speech. We'll all be better off in the long-run.