Japan is weird when it comes to LGBT. Homosexuality has been legal since the beginning and its fairly visible in their culture in various ways, which is more than can be said about many Western countries. And we all know what kind of sword fighting many samurai did with their students wink wink
But they have this weird "don't take it seriously" thing going on. A bit of the "don't ask, don't tell" mentally, too, perhaps. Well, at least they started with this partnership certificate thing, so there's certainly movement there.
Frankly, if you look at the global situation those last years for "first world countries" I'd wish politicians would just get "it" over with. It's clear where the wind is blowing, and countries pass laws one after another. Might as well stop delaying, it's not a development that's going to turn around any time soon.