Most people with these questions are basically wondering one (or more) of:
- Am I doing something stupid, or is it really broken?
- Is there a magical trick which will avoid needing a real repair?
- If no magical trick, is DIY repair possible?
- How to do a specific DIY repair?
- And how would the DIY price and effort compare to sending it in?
- And, is it worth it?
Of these, only #6 is really problematic, since that's a personal judgment. #5 might be also be hard to answer, but there are cases like How much does it cost to replace a DSLR shutter? which seem useful and have helpful answers.
For the others, I don't think answering with "here's how to contact a repair center" is really a helpful answer. If the answer is "it's broken, there's no trick, and you can't really DIY", that's fine.
I do understand the general irritation, though, because (especially as you get to outlining specific repairs), these aren't really photography questions... they're gear questions, and "camera repair person" is a different job/skillset/hobby from Photography. So, there's a case we could make for just calling repair questions off-topic. If we want to do that, I think having a custom close reason pointing to a meta question listing the resources James Snell suggests is better than using "duplicate".
If we do decide to leave these as on-topic, I think it's better to work on canonical answers for "stuck zoom", "lens error", "mirror stuck", "doesn't turn on" and whatever else. (And yeah, in some cases, that canonical answer really is gonna be "in this case, you need to send it in" — again, that seems fine.)
Finally, another thing we can do is really work to make sure the troubleshooting tag is on each of these questions. See What value does the [troubleshooting] tag have? — then, people who really hate these could add them to their list of filtered-out tags.