That's missing the point. Sealioning doesn't mean "provide details", it's shorthand for an argumentation tactic, which enables its practitioners to argue successfully "against" a position without evidence simply by demanding evidence from someone else. Someone coming in to sealion a discussion doesn't actually want the discussion to be had on the basis of details (because if they did, they would be providing some). They want to shut the other person down without having to go through that trouble.

Essentially, sealioning (as understood in this context) in an attempt to suppress dissent. And that's bad, no matter what tactic is employed.