Given that, at this point, there's no incentive for him to be a bastard besides the pleasure derived from it, it seems like that's actually just who he is.

or the persona he was given by the coverage...

For example, President Ford was probably the most athletic President in the 1900's (he played LB). He is "known" more as clumsy and un-athletic from a set of comedy sketches[1].

1) the real lesson is shoe choice is important as a politician