The show's likely written by straight dudes who probably consider themselves allies. The creator is the same dude who created Shameless US and reworked Ian into a resilient, more alpha version of his British doppelganger (at least in the early seasons).
I think the male nudity is pretty good, especially from Ben Robson who seems fine with nudity at any moment. RE: the gay sex, I actually think the show does a good job with that, too. None of the sex scenes are too graphic, so it doesn't make sense that the gay ones would be.
In terms of audiences, I think straight guys are becoming more comfortable with LGBT rep in general, but it's important to note that the kind of gay characters we're seeing in these type of shows are almost never the... let's say, more flamboyant type of gay dude. As you guys noted, Deran seems like a straight dude on all accounts and that is definitely intentional.
That said, not every person who watches this type of show is a straight guy. I only found out about because of a girlfriend who hyped it up, and I probably would have loved it even without Deran (though he adds a lot and I love the rep).