This is what seems to cause “You're posting too fast. Please slow down. Thanks.” to appear for up to two hours. Fittingly, I had to wait two hours to post this comment.
You’re twisting the issue by calling it “bad-faith commenters” though. Just take a look at this thread, where even the most polite, yet critical comments are downvoted and quite fittingly really hard to read.
This is what seems to cause “You're posting too fast. Please slow down. Thanks.” to appear for up to two hours. Fittingly, I had to wait two hours to post this comment.