1. Labeling someone a "sealion" doesn't even hinge on their opinion. You seem to have missed the entire concept, and instead interpreted it as a generic dismissive.
2. Uh, you don't get to just call something a "fallacy" because you don't like it (though many others are doing the same thing in this thread).
Sealioning is a reference to the specific disingenuous process of spamming the same low-effort, low-brow, easily-answered questions in every last public forum. It's a basic disinformation technique to spread fear, uncertainty and doubt.