I think you underestimate the willingness of people to pay to troll, it may filter out people but an app that was (in theory) meant to be secure shouldn't think of a problem as filtering rather than securing. Admins knowing peoples' identities simply moves the weakest link in the chain to the admins. I think an app like this was doomed from the start and 4chan simply pulled the plug on an already leaking bathtub.
I've thought about buying throwaway phone numbers just to troll linkedin. I'd be surprised if people weren't finding ways to get accounts on apps like this for trolling.
The only reason I haven't is because it feels like LinkedIn may have already jumped the shark and I wouldn't really get the value for my money.
> Admins knowing peoples' identities simply moves the weakest link in the chain to the admins.
And now you have a better chance at pointing a finger at someone, at the very least. And the thought of that finger pointing would be enough to keep an admin on top of things.