Consider your second expectation falsified and update on it, as a "bayesian rationalist" would.

I expect them to not care due to this being LW.

The choice of a name can provide some evidence about whether it's a good-faith account or not; and the name "troll" is providing evidence against. If you told people why you chose that name that might serve to counteract the effect, but I think you've not yet done so... Needing to justify your nick may seem unfair to you, but consider it from the point of view of someone who doesn't know you.