I think the pastor, or the head usher, or someone in authority who knows this guy and has had some interactions with him, has to have a stern word with him and tell him that holding and stopping people is not OK and he needs to tone it down a notch.
I know what you mean because many big-city cathedrals I attend have these guys. Sometimes they come in for Mass but they often aren’t praying - sometimes they’re just sitting, or sleeping in the pew or the corner, or at worst they are looking to steal from a purse. Usually they’re harmless and I’ve spent a lot of time in cities so I’m not very intimidated by them, but they can come off as scary to somebody else who’s not used to that.