You have to roll with it.
It's often a combination of different things. I've asked questions on things before where I'm technically in over my head - eg on a NAS drive where I'm getting answers that are probably helpful but I'm to thick to understand. And the simple answer I'm looking for possibly doesn't exist, or I'm not communicating it correctly. ( However, I do try and remember to thank people or respond)
Sometimes people want an answer that suits what they want to hear and not what is actually correct. I worked at KEF many many years ago and was trying to help someone on a forum with a question on their speakers. I was sat next to the engineer that designed the speakers and was getting the answer to the solution from him. The OP was taking advice from someone else on the thread that didn't have a clue. However, it was clear that was what he wanted to hear so off he went. That was a real WTF?! moment. Took me a while to get past it at the time.
Other times, it's reading the person, particularly on hifi, if they are more subjective or objective. people get wound up by advice that is at the opposite end of the spectrum and often those advising can't step back from their positions either.
You see if for example when someone posts a question on turntables and gets back an answer that TT's are technically rubbish and they should get a streamer. Unlikely to get a thank you for that.
The help I've had on here though has been immense, and the like button makes it easy to post a thank you.
Sometimes I think people get involved in a number of threads and just forget. I've no doubt that I've done that in the past.
A signature of KIT can help a bit as it gives a person a flavour of the sort of answer they might get. EG in mine I've got valve kit so there's an immediate indication that I might not be the most bothered about a technically correct sound
There are enough of us that are grateful, so please do keep inputting