Uncontrolled - definitely. More to do with the failings of everything around him though.
Wildly irrational - probably, depending on your definition of wildly. Although stupid (and non stupid) people often make irrational decisions, so it’s difficult to judge. He is both stupid and makes irrational decisions more than you would expect.
I think most would view deranged as to be having some sort of dementia that prevents coherent functioning, etc or some sort of behaviour that seems psychotic.
I think his behaviour is psychotic, based on norms, for someone in his position. I just think it is more a function of a being despicable person and everything around him abandoning its role in not accepting it. Rather than it being simply derangement. If Biden had deteriorated to being ‘deranged’ to some degree, similar behaviour would not have been allowed.
I think he has the capacity to behave in a different, less ‘deranged’ manner when faced with significant push back, which someone deranged might not. He just has no reason to do so, as he doesn’t face that and has no moral compass to compensate.