A gay couple in a series today is as forced as a black woman on the bridge in the 60s. The people who complained about the latter are the same kind of people who complain about the former today and not even notice the latter. It's also the same kind of people who won't notice either in the future and complain about what ever. Star trek handled political topics very well from the beginning by showing it as normal and making it a topic in allegories, sometimes making it explicit like when Kirk and Bones talk about how the "cold war on earth in the 20th century never got hot" or how wrong the Vietnam war "was".

You want your star trek before it was political? You can't be talking about TOS, not even the first pilot. Maybe the intro?