There are things I wanna up-vote and you don't need to be a certain level on reddit to do that, so why not make it slightly easier to participate in what we as the community like on here, it shouldn't be abolished completely because of spam bots or jerks. ( I am saying this without having used reddit.)
I doubt bots or jerks would buy experience boosts or grind to get level 20 just for shitposting or spam downvotes.
It's simply to avoid people using low level smurfs to mess with ratings/approvals of things on GP+ (I'm assuming you're talking about G+, but even in general if another board has that requirement, it's probably for that reason.) There's such a small amount of genuine low levels that we felt as if it was a safe way to add a precautionary measure to threads there.
Most true pre 30s rarely post on the boards, it's more of a precaution and seeing how easy it would be to just spend a few days getting to Lv 20 opposed to like a week+ to get to 30, it doesn't really seem that steep of a penalty.
