I see that several of you mentioned that the user is banned... but I don't understand something: is there any connection between being banned and having those posts hidden...?
I think that I've seen before at least one user being banned and all their posts being obliterated. But I don't remember details.
So I would say that yes, there must be a coneection.
And from what I see in the trust feedback, the mentioned user was evading a ban, so probably it's part of some automatic "punishment" that didn't manage to "reset" everything.
Maybe a mod knows more...