Newbie here, everyone is telling me to stop playing for my good

I started playing LoL about a month ago. Not much of a tryhard, I prefer a more casual way of playing. I'm seeking advice from other people who played this game for years, though they all tell me things like "stop, you're still in time, don't get involved in this shitty game". I know it's kind of a joke, but is a joke so big that makes every single player tell me to stop? Is there something I must know? People talk about LoL like it was some really strong drug.