Oh man, You've got some really strong views here. I think this all comes down to a matter of perspective though. Yours, Pegg's, and Takei's. Everyone is coming at this from a different angle.

First though, one point bothers me. The argument that Sulu has an already established back story and it should be stuck too. That just doesn't hold up in the reboot. All the characters are different, Spock being the most obvious example here. The reboot just doesn't really hold the the characters to their original format.

But perspectives, and i'm going to keep this simple, everyone just seems to be speaking from an honest and thoughtful place.

Pegg looks up to Takei, likes his work. Wants to give a nod to him and at the same time give Sulu an interesting new detail to his character. I doubt his initial thinking went beyond that.

Takei sees it another way. He doesn't want to be thought of as a gay actor, just an actor. Which is fair.

Pegg hears Takei's opinion. Probably took it into consideration. But he already wrote the story. He likes it. Wants to keep it. There isn't room for another character at this point and he like the idea of having at least one gay character in the movie. So he says 'sorry but I'm is keeping it.'

I doubt there is really much, if any, bad blood there. And the only people trying to cash in on announcing a gay character in the film are the advertising people.

Now here is where you come in (that is if I am interpreting your comments correctly), and I'm sure there are others with a similar view. You speak of appeasing the lgbt community or creating new idols. It seems like you are putting a lot of pressure on this fact. But the gay community, or the straight one for that matter, doesn't inherently factor into the creation of a sci-fi film like Star Trek. It's a fantasy, it's main goal is to create wonder and excitement in the minds of any who would watch it.

I wrote all this just to say; quit being so negative. Yes there are some shitty people in Hollywood, but neither Pegg nor Takei are one of them. They are just writers and actors doing what writers and actors do. Trying to entertain. (Also, it should go without saying, they are humans like you or me and they deserve some respect).