Was it mockery, or merely a reminder? They should talk about that more deeply some time, when they're not so drunk. Loki has a tendency to make light of the things that cut him the most deeply, with only a few exceptions. Maybe, with Thor himself absent by necessity, he just wanted that reminder for himself, to pick at old wounds at the same time as they attempted to heal.

Loki is complex and contrary and his own worst enemy.

But he will not be his alternate's worst enemy; on that he is already decided, and he looks up as Thor leaves to find him, with a small, soft smile of approval. He has time for reconciliation. The other Loki may not.