Is it possible to have it be a bannable or punishable offence if users refuse to contribute any useful information to the site, and refuse to accept any criticism on how to improve, especially if other users have offered?
I don't believe this in particular should be bannable. I don't want people messaging us saying, "This person isn't listening to me, can you tell them off thanks?"
You don't always have to accept criticism and not everyone agrees on what content is useful.
With that said, it's very reasonable for us to talk to people for not following basic forum etiquette -- "stay on topic", "do your research", etc. We have definitely banned people before for posting garbage comments over and over while never responding to messages from us about that. (The key is people who don't respond to us. We will try very hard to make you notice our messages and hopefully act upon them before we ban you for something like this.)
As far as "low effort" questions go, e.g. issues that very clearly could be solved with google, hopefully closing them over and over is enough of a deterrent. I have some sgt threads to finish writing that might help with this too (and I'd put some stuff in the rules list as well if I had my way).
The short (but unhelpful) answer is we will always respond when we think there is a problem. If we think somebody's posts are a disturbance to the community, then of course we are going to talk to that person. There are people we've banned that you would never have heard from, because we removed literally everything they posted. We're definitely trying to keep a standard for content here.
I'll quickly add something, because I know one person in particular is on people's minds right now: I personally will not demand people to select answers to their questions if they don't want to. If you answer somebody's question, they don't select it and never tell you why, that's tough. It's their choice. You are not owed the 20 points.
