I'm not going to say it necessarily applies to this game, but it really seems like there's an odd trend of high quality games putting out a couple updates and then stringing their donors along for a year or more.
I noticed the same thing. What I've realized is that it's what you're incentivized to do as a creator in this entertainment genre. People get excited by a string of great updates, subscribe, and then either forget they've subscribed or apparently are fine paying in exchange for nothing. Whether it's forgetfulness or being a sucker, either way you're not really rewarded as a porn game dev for being consistent with your content production.
The other aspect, I think, is that devs are taking on projects in this genre with insane scope relative to their staffing. Usually it's just one dude doing it in their spare time, and it's not shocking that they struggle to meet expectations in terms of schedule.
Then the final part is that because it's an understaffed team (or individual) working on a project with major scope, eventually they become exhausted and/or personally disinterested, and the whole thing dies or gets wrapped up prematurely.
I think we're seeing some signs that the genre is "professionalizing". Cure My Addiction, Become a Rock Star, Being a DIK, and the Treasure of Nadia people/teams are all high-quality and very consistent with their updates. I suspect the "market" is going to start to have higher expectations, too - I think you're going to see people become a lot quicker to pull the plug on Patreon commitments to devs who don't consistently hit their update targets.
