Honestly, this all comes back to the issue "Why is the person who does the majority of the programming also doing the majority of the customer support?"
Let someone else close issues that are offtopic or a bad idea. He insists that this means that 'you have more people who have to read everything' but it absolutely does not. It means you need to learn to trust that if so-and-so closed it, it should be closed.
> "Why is the person who does the majority of the programming also doing the majority of the customer support?"
Because no one else cares. It's a huge problem in Open Source projects. Most of them are single-person projects. One person does the coding, bug fixes, releases, documentation, and answering questions on the list.
For the OP on github, he needs to learn triage. There is no reason to be polite to people who can't be bothered to read the documentation. My mantra is "if you don't care enough to put some effort into it, then I don't care, either. Go fix it yourself."
He needs to quickly read issues, and close the idiotic ones with minimal comment. If they keep arguing, block them.
A good project maintainer can't afford to waste his time on loud-mouthed idiots. There are too many quietly competent people who need his time.
Let someone else close issues that are offtopic or a bad idea. He insists that this means that 'you have more people who have to read everything' but it absolutely does not. It means you need to learn to trust that if so-and-so closed it, it should be closed.