Got My Champ Banned In Champ Select, Then Got Hit With A Presentation In Chat

So I just queued a draft game, picked my Nami in champ select, only for this person to ban her for no reason whatsoever and then post this link in chat: https://docs.google.com/presentation/d/1oKtfhkQd6-rFs2REh1FTRl3_zG0FtugFJSutkFKBs64/mobilepresent?pil=1&slide=id.p

I can't even comprehend this shiz. Is this normal now? Banning your teammate's champ intentionally for fun on the regular? And apparently this is not punishble at all and I'm the cringe person if I don't handle it 'the right way'. I don't know what to say, thoughts?