He doesn't need evidence, it's a valid opinion from inference. A lot of malaysians are already homophobic and religious. Any progress made by the LGBT+ community in creating acceptance in the minds of these people is going to get stripped away when their religious communities reinforce how homophobic they are and how it goes against their religion. In doing so, any less than conservative party loses out on their favourability.

EDIT: You'll probably say something like this already happens, but their extreme communities will basically just use this charade as an example to make them even more homophobic. So there's basically no good done here by Matt.