In Lai's letter, the author reasons that homosexuality is detrimental to society because homosexuals aggressively promote their lifestyle, which the author adjudges to be decadent. But a person's lifestyle is one's personal matter, how can one say so convincingly that it is either moral or amoral?
I do agree that aggressive promotion of anything is very annoying especially when the one promoting disrespect for the opinion of the other person. However, I have not yet come across any homosexual trying to convert anybody into adopting his or her lifestyle or beliefs.
This cannot be said though of certain religious groups which claim to be the pillars of morality but blatantly disregard other people's beliefs in promoting their own religion. If homosexuals are to be disregarded because of their apparent aggressive espousing of their negative beliefs, then, I do not see a difference between homosexuals and these religious groups.
One cannot classify another's activities as immoral or negative, purely because he or she is different. Everybody should have the right to voice their opinion, and whether or not the rest of the people listen, it's up to them.
If you deliberately undermine the rights of a group of people purely because they are different from you, you create an environment of oppression and hate. Neglecting certain groups of society will not work either.
Only through acceptance, active discourse and engagement to deal with issues of every group of people in our society will there be a modern and civilised state of being for everyone.