Watching a show like that (unless it's just to be horrified) absolutely says something about your intellectual capacity and your leanings.
Your leanings? Absolutely. Your intellectual capacity? Not in the least.
While I personally think homophobia is abhorrent, I acknowledge that there are lots of people who are objectively intelligent (in the sense of having high IQ scores) who nonetheless disagree about the politics. I may think these people lack critical thinking skills, but more likely their cultural background has not prepared them to think critically about the issue. I also, for example, believe that there are extremely intelligent people on both sides who radically disagree about one simple fucking sentence - the Second Amendment to the US constitution. I think it's pretty clear (why else specifically mention a well regulated militia?), but lots of other smart people don't, so I don't say they're stupid because they disagree.
Consider, for example, that - had you asked them in their historical period - almost certainly Gandhi, G.W.F. Hegel, Martin Luther King Jr., Isaac Newton or John F. Kennedy would not have supported gay rights. It's not because they weren't smart, it's because they came from a background where they just weren't prepared to consider it in the same set of assumptions and contexts as many of us do today. For example, I can call Israeli settlers on the West Bank of the Jordan stupid because I believe they are "on the wrong side of history" and are harming their nation's cause in the eyes of the world; but I acknowledge that some of them may be very intelligent and - had I been through the same things as them or brought up in the same environment - I might feel the same way.
So while it's easy to say anyone who watches a show whose protagonists disagree with your views must be stupid, I counter that it's just that type of generalization which is stupid.