There are only three scenes with Sulu's "husband" and daughter in the Star Trek Beyond. If I haven't heard about the controversy before seeing the movie, I could have assumed that the "husband" was Sulu's brother and maybe the daughter was his niece. The scenes are quite subtle. No kissing, no glory holes, no rainbow flags.
Why even bother unless it affects the plot in some way? Just to be fucking lame. The problem isn't making him gay. The problem is making him gay for no reason other than to pander.