This is not any different that outing Anthony Weiner for being straight. If you are a politician, you should, probably, try to avoid sending pictures of your dick to others. Or be prepared to have that blow up in your face.
The problem with Weiner I think was more that he was married, and apparently cheating on his wife.
The problem with Weiner, of course, was who that wife was
But, in general, the problem is always that the person in question does not want information about that sort of behavior becoming public, for whatever reason. If the politician is not trying to conceal anything (for whatever reason), there is no problem.