I debunk things if I see a mistake in them that's not been clearly addressed. I really don't consider the issues on your list. I usually end up addressing topics that I've got some interest in, or are tangentially related. Often I build upon the debunking efforts of others, but try to make it more accessible.
The key consideration though is if there's some bunk there. i.e. if there's a mistake or a lie - like "contrails always quickly dissipate".
But you also get really bogged down in the petty Mick. It makes you blunter than you are sharp. So rather than debunk facts, you question the poster's motives, experience understanding etc. I hope you strive to improve on this fault I think you are better than that