My guess as to why it happened back then and doesn't now is that back then people still had Noxian Nights in mind when they thought about Hreinn Games, which was (and still is) one of the best h-RPGs imho. So the hype about their new game was big, but KoD just isn't what people hoped for I guess, so the hype stopped.
I personally hope they return to RPGMaker after KoD, not only because I personally enjoy RPGs way more than VNs, but they are way better at making actual playable games and not VNs. Plus, at the start of KoD development they thought about going back to RPGM, and also possibly the LoL-Universe, which I hope they still plan to do.