do you know why nunu/singed got banned?

its because those 2 actively sought out their support role and did it tons of times where it had to be manually audited because the auto ban hammer system couldn't figure out what was going wrong.

but your first time rammus sup bot laner who feeds all game long is aces and even if 9/10 players report him, nothing happens, you need a history and a large volume to make a difference. riot doesn't look at one off games, they really dont.