This has been an ongoing issue for a long time now. So I don't know why people are still complaining, like it wasn't expected. This Dev will take his own sweet time to update the game, and I don't see any complaints, either here or on his patreon site changing that. It's his game and therefore it's his right to take as long as he wants, and ignore any criticisms if he so chooses. That's definitely not the best way to encourage people to become patrons, or stay as patrons. But if he hasn't got that message by now, it's obvious he never will. So why keep going on about it?
Either he'll update the game or he won't. I'm not a patron, so I'm not owed anything by this Dev. I'm just grateful when content comes out, whether it takes a month, a few months or 8-9 months. If you're a patron then it's a different matter, but there's a very easy solution, just cancel you're subscription if you're not satisfied.
While you're waiting for this Dev to decide whether he wants to update his game, just play one of the thousands of other games on this site. There are almost limitless options, many of which do get updated regularly.