Do you notice when a blatantly heterosexual couple are placed in a movie?

In a bad movie? Sure. These movies are usually to be categorized as "mediocre rom-coms" and are just as uninteresting for me as lazy scripts with non-straight couples. You are welcome to argue that the latter deserve more attention because they at least attempt to normalize homosexuality – but then I will reply again that the brazen normalization attempt in tandem with bad plot and uncredible characters makes the movie even worse.

Similarly, do you complain when a ham-fisted attempt is made to put a right-wing political message into a story? Or are you content to ignore the money and energy spent on, for example, pro-military interjections?

Unsure which movies specifically you have in mind. But yes, it might be that Rambo & Commando-kind of movies provide me with a lot of fun – more than they should, really – even though their cinematographic value is pretty, pretty low.