+i remember encountering this situation quite often in school. a fellow student would ask a sincere and appropriate question, the purpose of which was to clarify something the student (and maybe others) was unclear of. they would get an answer that was equally unclear and mostly BS. and because BS compounded with BS more often than not leads to contradiction, i would often ask for a clarification and point out a contradiction or two. as you can imagine () at this point the instructor would, most likely, realize that THEY really didn't fully understand what they were trying to explain, and rather admitting such, would get ticked and cut the conversation short with even more BS.

now, when someone lights up my BS indicator, i just tacitly write them off as a potential source of useful information and carry on. (usually )

BTW, i've found this behavior is universal in the animal kingdom, generally.