I’ve heard both.
I’ve heard from various sources that he is very charming, witty and likeable.
I’ve also heard, from numerous sources, that the affable buffoon act is entirely an act and that is very sly, condescending, impatient, rude, bad tempered and just downright nasty.
I don’t know which I believe.
The two descriptions are very different, but of course everybody has good days and bad days.
I’m inclined to believe the former.
I think if he was genuinely unpleasant to people he wouldn’t have got as far as he has.