He isn't saying "you must leave or else," he's saying you don't make any sense by whining about how League is pointless to play when you aren't playing it (which, you're probably lying about considering your random bout of salt in your original post)
1.) The point is to stimulate your brain: using strategy, learned muscle memory, and pattern recognition to do well. People who enjoy competition have lots of fun, you're clearly not one of these people
2.) Getting reported by players means absolutely nothing if there isn't content to act on. If you're kind in game and get reported by all 9 other players to troll you, the most you get is a message saying you were reported. Nothing else will happen to you. So it doesn't matter if you get reported as long as you're playing nice.
Yes, League does need work in terms of IP earning and rune costs, but it doesn't make the point of playing irrelevant.