Bagpuss
Legend
Dissension does not entitle you (generic you, not Mistwell in particular) to engagement with any particular person or discussion.
Hmm I think if they are expressing their view on a public forum, be it somewhere like here, reddit or twitter, then you are entitled to respond on the same medium.
In most cases if they don't want to engage, they can simply ignore the person, or actually use the websites block/ignore features.
Claiming sealioning is more for the other people watching the discussion to try and turn them against the other speaker, without addressing their point. Actual methods to protect yourself from harassment are built into most social media platforms, but don't turn the crowd against your opponent.