may you and the people relying on you never have to rely on the maintainers taking things more seriously than they've shown themselves to in their public positioning
He has no such obligation to do these things, this is all his choice. I'm not sure why the contention? If you read my comment, it was strictly about production scenarios, not about all credibility for all scenarios. If this project is meant to be treated as fun CRAPL, Matthew Might made a great license for that: https://matt.might.net/articles/crapl/ .
I still hold the position that the social media presence of the project should be inconsequential for considering it's production usage. But I can see your point now, even if I disagree.
2. The joke made by the maintainer gives absolutely no insight into how they will behave if there were a contract. If anything, that might mean the maintainer actually is a human that is agreeable to talk and work with, because they don't take it so seriously as to forbid any jokes.
Professionalism doesn't mean "no jokes allowed", it means "do your best".