[the_jeremy]

If you ask a bad question on SE (leave "bad" to be defined separately), you waste time of people who try to answer it, and of people who stumble across it hoping that it relates to them and solves their problem.

If you ask a bad question to ChatGPT, you waste no one's time but your own.

If answering SE was a job where you got paid, I would expect a lot more hand-holding (and some amount of kindness, to keep the revenue stream coming back), but instead, the people who answer questions do it more-or-less for fun. Having someone waste your time isn't fun.

[dotnet00]

In those cases it's easy enough to just move on to another question rather than shut down the discussion. It's not like anyone's being forced to answer.

[the_jeremy]

But as an answerer, you will empathize more with the other answerers than the askers. You don't want the other answerers to also waste their time on this question, so you close it / downvote / mark it as duplicate.

[bhandziuk]

But by being closed as a duplicate with the duplicate linked hundreds of future askers who arrive at that question in the future from a search engine are saved the trouble.

[dotnet00]

The posts being discussed are cases where the question is marked as duplicate for being vaguely similar but not actually the same. Of course marking literal duplicates as duplicates is fine.

[d0mine]

The primary (95+%) use case for Stack Overflow is being the destination for a web search. "Bad" questions make signal/noise ratio worse.