Ah that sounds terrible. TBH I've only been lurking this sub for about 4-5 months, and made my first comment here maybe a week ago. Most of my lurking involved searching through old threads for discussion about things I might need to be aware of so I have not had any negative reactions or anything, but I did see quite a bit in my searches. People getting downvoted for just asking if X or Y would be better, things that I find unacceptable to be downvoted for. It has made me quite wary about asking for advice and I've felt the need to explain myself and reasoning behind everything I say/ask.

So in the succulent sub I try to stick by some "rules" for posting advice about plants which are looking horribly unhealthy. I start out with a compliment, like, "that's a beautiful pot/plant" "you are doing great with light" and THEN I get to what needs to change, and try to end the comment on a positive note. For example, for a plant that is in really bad soil and is looking seriously overwatered, I might say something like this:

"Wow! That is nice and compact, you are really nailin' the lighting for this bad boy. I think for ultimate happiness though, you may want to consider upping the grit on your soil because (detailed explanation on how succulents thrive in the wild, what to use, how to do it safely, and how I can tell it needs to be done.) If you change that, you're almost guaranteed never to overwater and your succulent will be it's healthiest and happiest for a long time! Good luck!"

When I catch other people being rude in the comments (not often anymore) I will not directly respond to the rude person (unless they are being downright hateful, but then I also report them.) I respond in my own top level comment or a direct reply to one of the OPs comments apologizing and assuring them that that kind of treatment/talk is out of the norm and unacceptable in the sub. I then give them good advice, wish them luck in the future, and ask for updates, if possible. I really try to get the point across gently that the succulent subreddit is friendly and helpful and we WANT people to experience the joy of growing beautiful plants. I try to word things in a way that the douche doesn't even respond and I guess people want to feel friendly and helpful rather than a douche bc I've never been sided against. I make sure that I'm not directly or indirectly being an asshole BACK to the original asshole, kill' em with kindness. Might also help that I'm up there with the top contributors of the sub so the power users here may need to take some initiative to make their sub more welcoming. I see that the mods DO take action on some of the assholery but there needs to be more than just "be nice" in the rules. I'm talking about a temp sticky on the way to give care advice with compassion.

Yeah whatever it gets tiring to give the same advice over and over, I KNOW, I do it all the time on the succulent sub, but if you're having trouble remaining friendly giving advice, maybe give yourself a break for a while and stop giving advice. Fatigue from answering newb questions is no excuse when you are literally volunteering your time here and can just, not.