If he's unhappy, why doesn't he step down? That's what I did as libxslt maintainer and what I'm about to do as maintainer of libxml2.

There are degrees of unhappiness. There's no reason to assume a binary of loving everything about work or hating it so much that they'd be happier without it.

To be clear, this isn't intended as a criticism of your choices to step down from maintaining various projects; my point is that these choices are quite personal, and it's not always going to be obvious how to balance the tradeoffs. It's entirely possible that they are burnt out to the point that they might be happier in the long run if they did step down now, but it's also possible that they might be even more unhappy giving up something that they care a lot about and are willing to tolerate the less fun parts. I suspect you could provide a lot of valuable insight on these sorts of decisions given you experience, but even from having to make similar decisions for things with a tiny fraction of the exposure of the projects you've maintained, it's clear to me that there would need to be quite a lot more nuance in analyzing a situation like this, especially from the outside.

I think he's just pointing out current problems, as he's done many times. He likes to give talks and publicity to his project, as its maintainer, and that includes this sort of "what's going on with the project" talks.

I don't think he's unhappy. Frankly I think he's doing the right thing, and I say that as the founder of a project where I didn't do that sort of thing, but now realize I should have. This is what gets you contributors/donations/publicity.

He's not unhappy