Did his comment really muddy the waters?
Taken absolutely literally, he asserted that the problem with video games was the proliferation of marines who travel in space rather than over water, and said marines engage in an alternate sexual lifestyle. Sure, I could also interpret the statement wherein the word "gay" is assumed to be a pejorative, in which case the comment becomes that video games have a problem with the proliferation of lame, boring or stupid marines who travel through space rather than over water.
Either interpretation makes a valid point I'd say. The bromance is indeed strong with many of those marines so I might interpret them as possibly being homosexual. They are also often entirely interchangeable characters which means I could easily call them "lame" or "rubbish" or "boring" or any of the other pejorative interpretations of the word gay.
And, while I can understand why people might get mad (the word gay is being used as a cudgel in either case), it strikes me as strange that we so rarely apply such arbitrary interpretation of language. The word space, for example, does not necessarily imply that area outside the earth's ionosphere and can instead refer to a basic dimensional concept. Taken to the illogical extreme, I could interpret his statement to mean something along the lines of: the problem with video games is the proliferation of lame water areas, a dig at the regular inclusion of bodies of water in many video games.
But, I don't do that because I have this amazing capacity to critically read and don't just assign arbitrary meanings to words; instead, I use the context in which the words exist to determine what the writer or speaker might have meant to say.