It's not always toxic. If someone on your team wants an extremely OP champ, but they're last pick. What do they expect? It'll make it to them? Likely they won't even get to pick it anyway, which is the same as having it banned against you anyway. "... you get a free lose mate". Sorry this is the 2nd video from this guy that I've seen. Pretty much think that he'll never have any reasonable ideas because he just seems so toxic. Like he's a stereotypical frat boy from Hollywood or something.
If someone bans someone, it can be because they just don't wnat to play with or against it. It is their ban. I bet this guy would also say "tough shit. It's my pick" if he picks a champion people don't want to play with on their team... but when it's in reverse, and it's not HIS decision (aka the ban), he feels like he has some say in it anyway.