It's clever timing to come out at this point.
His sexuality has now become more of the talking point rather than what he did - and the narrative changes and suddenly he becomes more of a 'victim'. And any criticism of him - that was already happening and seen as perfectly valid given the circumstances - now becomes re-interpreted as homophobic.
Had he remained what people thought - a straight, white man - he'd have continued to have had no sympathy for his actions. The fact that he's now a homosexual man changes the narrative as he now falls into one of the demographics that will get much more public support and backing.