I see the overabundance of ecchi as a byproduct of low birthrates rather than the cause. Because more and more Japanese people have stopped pursuing romantic lives, media has sprung up to feed off their sexual frustration.

Is that the actual reason why birth rates are declining? Or is it just a meme?

Because from what I've read, the problem has more to do with the social and economic conditions that come with the cost of forming a family in Japan, it's just more beneficial for people there to stay single.

I'm not an expert on the topic, though, I'm just wondering.