I had a player feed today because I played an "Unviable Champion"

Had a Trundle Top intentionally feed, intentionally diving a Garen under tower when he knew he couldn't, refusing to leave top lane, and as a member of my team eloquently put it, was "Acting like Tyler1", because I picked .

He told me not to because "She hasn't been viable in 2 years". I didn't say anything until he insisted, at which point I quoted both Trundles and Kat's win rates. I also said that it was a normal anyway, and we're all silver so "Viability" isn't even a thing, and he proceeded to go into full 12 year old rampage mode about how we weren't playing to win. I muted him but I guess he was toxic the entire game. He fed the lane opponent really bad, and I guess was blaming me the entire time (As evidenced by the enemy vayne's comment "stfu she's 12/2").

Please, if you act like this don't use chat. Like, if I am picking some dumb shit like AP mid in a ranked game, by all means flame my ass off, but if I am picking a champion whose literal meta-role is midlane, and you start flaming me for "not trying to win", in a normal of all things, just don't.

Edit: I was mid lane kat, not some weird shit like ADC or support