"Doesn't matter if you agree with what he says or not, you should defend his right to say it (even if he later retracts it :p )."
"He made a stupid comment that some found offensive, nothing more and nothing less. Get over it"
No, he felt his position of power and privelege allows him to encourage others of the same mindset to abuse and denigrate a section of society he has issues with. He has put his hand up and declared himself to be a disgusting bigot of the first order and deserving of all the ridicule and reprobation he has since received.
As others have said, whether serious or not, his purpose was to promote the subjugation of homosexuals just as the Nazis did the Jews (and others) and as white Americans did to black Americans. The difference between the Nazis and this bigot is that where the Nazis picked on people who had made a lifestyle choice, he wants to attack people for something that is inherent. Which makes him even more despicable. The only reason he didn't include blacks or women, who have also borne the brunt of religious bigotry, is that, by and large, you can easily tell whether a person is black or female without additional tagging!
Being gay doesn't make you any more of a threat to society than does the fact that you might be black, a redhead, male, or female. It's just that some people who make a choice to follow a particular religion or creed often need to find some group of people they are against just to make themselves feel good.
Of course, he is free to say these things, so that we can then properly judge him for the idiot that he is and ensure that he is removed from any position where he might be able to convince other similar idiots that he knows what he is talking about!