Heh, if you find out how to not get upset, anon, let me know. I still feel pretty hurt at bad faith questions from friends. As if it has to be justified at all. As if the addition of these usually side characters has to be more than just, we exist, and for us many of us this will be the little exposure to queerness we get at all, and how this is a drop in the bucket compared to all media that exists and doesn’t make up for decades of exclusion.
And like, actually, every Netflix doesn’t, I know because I deliberately look for that. 😛 Ask him to list them and point out the ones that don’t have any. Ask him to list the number of straight characters they have even though you’ll both know that’s impossible. But some people that like to question more diversity move the goalposts because then it’ll be about how there are just more straight people overall, as if suddenly now realism matters. As if real life is filled with pretty young slim white people only. And if you point that out, then the argument pivots to what people “want” to watch, what sells. It just goes on and on.
If you’re out to him and he asks in a way that implies he doesn’t really want to know, if he’s sealioning basically, I wouldn’t engage. It’s not your responsibility to teach people. Just say you hope they add more and leave it at that. And if he does seem sincere, then just explain, what may seem to him like an explosion of characters is because he’s perceiving the increase, it’s still not actually that many, it’s just more than zero, and it’s valuable and important to you.
Although obviously this could be terrible advice for your friend, you know best how to handle him. But just to reiterate, it’s not on you to educate and open minds.