Whenever i play support my team just thinks i dont know anything about other lanes

Darius top lane going against ad teemo, losing lane at that btw. He builds maw, i kindly suggest that building maw would be futile as the only real ap damage is from mid lane orianna and not very good laning wise. He then says "Fck you, you are reta***d" and i explain that if anything steraks would be more appropriate for the match and he said "you are just a dumb support you know nothing" Why does everyone just assume that bc someone plays a certain role they dont know other roles? This isnt even the first time this has happened lmao