That's a pretty good sign that the HN user base as a rule finds most enjoyment in writing high quality content for themselves. All questions are legitimate, but in this circumstance what reason is there to believe that they would find even more enjoyment from reducing the quality?

It seems a lot like code. You can "vibe code" your way into an ungodly mess, but those who used to enjoy the craft of writing high quality code before LLMs arrived still seem to insist on high quality code even if an LLM is helping produce it now. It is highly likely that internet comments are no different. Those who value quality will continue to. Those who want garbage will produce it, AI or not.

Much more likely is seeing the user base shift over time towards users that don't care about quality. Many a forum have seen that happen long before LLMs were a thing, and it is likely to happen to forums again in the future. But, the comments aren't written for you (except your own, of course) anyway, so... It is not rational to want to control what others are writing for themselves. But you can be responsible for writing for yourself what you want to see!