"Was googling some of the fine young actors in this show after seeing part 1, and I found that several of them identify as straight. It strikes me as odd that this sort of casting is still happening - and especially with a gay lifestyle/history play like this. Also, makes the Sean Penn/Harvey Milk line feel particularly awkward. I'm not yet able to articulate the nuances as to why this feels 'wrong' to me."
Perhaps because it's not wrong, or even "wrong." If you spend some more time thinking it through, I hope you will come to understand why it's not wrong -- although I do think it is valuable to have the discussion, as long as people try to keep their emotions in control.