It's true that development is slow, but the developer never promised it to be fast... Why should he if people continue paying?
Also, there is one important thing to understand, that NewLife is a sandbox game. While visual novels are mostly paragraphs of text, a sandbox game is mostly code/logic.
Adding a paragraph to VN is pretty much a case of clicking Ctrl+V, while a sandbox game requires numerous lines of code laced through "content", possibly a rework/edit of an older codebase surrounding the new mechanic too...
I don't have personal experience writing stories (VNs) or games (like NL), but if you spend some time to learn a bit about it, sandbox is around 10x harder to develop than a VN.
Cheers.
The problem is it is a very shallow and repetitive sandbox, very superficial, so may as well just be an interactive novel as you will come across the same sequences and descriptions over and over again even in one playthrough. Feels something of a grind. When you add "skip sex scenes" to your
porn game as a feature because they are too boring for the players then you've admitted failing its main purpose. If someone can't do it after several years and other devs can churn out several IFs or VNs in that time with far more novel content then what's the point of the project? Reading the same lines over and over isn't much of a sandbox more than playing the same VN is. And yes, your first line in that post sums up the problem with this game and all the patreon pay pig systems with poor work ethic or project problems - why should they work hard (or at all?) when the money flows in from horny customers hoping they'll get some scraps eventually? It's basically welfare from horny people. We see even cancelled and abandoned projects keep their patreons up to keep the money in even years later. Morally it is cynical at best and bankrupt at worst way to approach things but if all you care about is taking someone's money any way you can then whatever. The developer did have a different approach and output early on, with more rapid updates, more signficant updates back then and the regular update schedule that appeared to promise good things. It's obviously become a struggle for whatever reason for SO. I think the problem is not that the developer approached this with any kind of "scam" in mind at all but rather that they stumbled into relative success but lack the ability and discipline in coding to fully adapt to it and keep it going and is probably a mental drain to boot at this point.
What happens is typically an overambitious project, a "my first project" terrible spaghetti code foundations laid down that becomes the backbone and then they want to add content WHILE trying to build the skeleton of it at the same time, to keep the subscribers and interest from watchers coming in, even if it is clearly a terrible way to code a software project. Even worse if you're basically learning how to code at the same time. Eventually you're years into a project that's now your only thing (possibly you've even made yourself dependant upon it financially too so you're scared to do anything to upset this apple cart) that's now a wobbling disaster and ever more difficult to update and fix. You're terrified of starting over or gutting it and rebuilding as that will mean a real normal dev cycle of nothing to show the public for months or longer and then a bare bone skeleton after, even if the structure for coding and future updates would be far better and the whole thing better for the customers in every way. It's doomed to fail in a long slow misrable dwindling mess both code and financially if the developer doesn't have the backbone to say "hell with it" and either start over with something new with all the lessons learned from the project (even as a side project to start with and migrate people...) or a rebuild while they still have an audience and some goodwill to tap into.
There's a lot of good crowdfunding usage and people who are very open about what they do and their tip jars and funding systems too. The problems lie with the customers and their naive behavior mostly, much like many of the kickstarter disasters that get featured in news from time to time.
The only ways I can see NL end is with a tragic long whimper or being taken around the back fo the woodshed by the devs and dealt with ol yeller style to be replaced with a much better new project (even if it is just NL 2.0). The latter would be best and would be best done before desperation and letting NL dwindle to life support status, with a handful of people still delusionally making more excuses for it getting slower and more bogged down in problems, probably due to sunk cost fallacies in action. It would be mentally better and good for morale. I bet SO at times probably dreads the monthly deadlines and having to juggle things to keep it going while struggling with code.
A more experienced coder would not have approached things as SO did, nor would they have had the same issues and performance. Perhaps with SO being more experienced now in the pitfalls a fresh start would be ideal. Think of the waste of time and talent having SO struggle for more years to....what? Another few text descriptions of outfits that make no difference to gameplay? A minimal scene that takes less than thirty seconds to play through and requires a billion special conditons and good luck to fire? When instead solid progress could be made with the right planning and tools on something else instead and let vision and experience shine not weighted down by spaghetti code chains.
Lillith's Throne suffered similar problems with the foundation of it (notorious performance issues even on good PCs, for instance), probably Girl's Life did too (both better and bigger in their own way than this game, tbh). There's a few that did sandbox in various ways better with more content already and lessons can be learned from many projects to make something new and better.