I don’t know whether you’re the same as the first anon, but again: you are imbuing belief with the magical power to change the world.
If you want to change the world, you have to do something active. Believing in what you want to be true is a laudable beginning, but it isn’t enough. If you want gay couples to be able to be shown on tv, there are a lot of things you can do about that. You can make noise. You can participate in critical conversations about the structure of society. You can talk to your own friends and relatives about queer representation and why it matters. You can send letters and emails to government and corporate representatives. You can offer your time, money or other resources to activist organizations.
But just wanting it to be true isn’t enough.
And none of that is likely to have much effect on Sherlock as a show in any case. It can change how future shows that may yet be conceived and approved will be treated (which in itself is important), but Sherlock is in a position where, most likely, that decision has already been made, one way or the other. All there is left for us to do is to wait and see what that decision was.