You see that a lot with 2e people -- bright people with some weaknesses or a disability. That could account for how negatively you have experienced this. Many 2e people have never really been taught good ways to handle the combination of big strengths and big weaknesses.

I serve as a sounding board a lot for my oldest son and that works well, but it's not uncommon for such people to just be trying to meet their own need to process information and/or feed their ego, oblivious to how it impacts other people and not really welcoming of the feedback they really need for this to be constructive. A good sounding board doesn't just listen, they ask pertinent questions and make insightful comments that help move the thought process along.

Sometimes when I meet people like that, I'm able to direct the conversation to a more constructive back and forth of that sort. But some people just know they have this need to talk, they have a lot of baggage that makes them openly hostile to meaningful feedback and they crave validation. Anything other than praising their half-baked ideas is met with toxic reactions. In such cases, the best you may be able to do is basically make a few polite noises and then disengage as quickly as possible.