Question

I'd really be careful on this. While you may intend it as a joke or in a playful manner, the enemy team may interpret it differently. I think playful banter is good, but if someone is obviously having a bad game or aren't playing well, you don't have to blatantly try to tilt them more. Such actions can be viewed as harassment. I don't think there is a difference, as if you tilt them in chat, you are most likely bming them. And if you are bming them, then you are trying to make them tilt.

There's a very fine line.

I see BMing as for example spamming laugh on teemo, a friendly taunt, dancing in front of your opponent when their are about to die, saying like "nice ult !!!" to someone who just totally missed their ult, things like that.

Saying "ez" when you killed someone for example is not BMing at all, anything that could be mean to someone isn't.

trying to tilt the enemy is a legit strategy that requires alot of thinking. find what tilts just 1 player on their team the most and exploit that. for example if you kill the same player over and over you could just say one phrase everytime like " lol good job". maybe that will get them to quit the game after while and in return also tilts the other players on his team etc etc. now the BMing part can have 2 extremes like after a kill you spam a emote under their tower and purposely die to it and keep spamming it. thats like hearted BM but can account a trolling so i wouldnt do it. and the other part is like saying " your fucking trash are you retarded or something?" thats the part extreme that is toxic and part of the lane you shouldnt cross ever because it can get you banned and to be honest it doesnt work as well as the other side as i have seen. so take it what you will