@MagmaDrago
more like ecchi+harem series are already in bloom since times immemorial (fuck it, sex always sells), or at least started in 2000s/2010s, but recently put into spotlight through memes and jokes on how recently the Japanese government officially recognizes that their national birthrate is declining fast, and their solutions to promote families into having children.
people just linked it through correlation and voila, it spread like wildfire, mostly propagated from out of Japan itself. seems like the publishers also acknowledges this and just jumped at the chance. if they do 'ordered' the publishers and studios to push more ecchi+harem series as one of their solution, IDK if I should laugh or do a standing ovation for it.
or maybe both.