Finishing a game isn't the issue. It's the regular updates that matter most. This particular game has a lot of content already there. Besides the girlfriend's storyline being unresolved, everything else is pretty well developed.
This game has more content than a lot of finished games out there as it is, but the Patreon model incentivizes games that seem to have unending scope. Think of some of the most successful games which have been in development for years like Summertime Saga, Four Elements Trainer, DmD, etc.
They're all constantly getting updated, and as long as the content keeps coming in then people aren't worried.
I dont know the others you mentioned but dating my daughter is from a developer who already finished a game such as melody, an old famous one. And he is developing 2 games now. Sunshine love and DmD. We already know his line and way of work.
And we know he started developing DmD without having someone to create the animations. Apparently he can't do it by himself.
Even with all that he never stopped delivering updates in both games.
I know the content of this game, but it took almost a year, or even more than that to have a new update, and it is, as far as I know, the first game he is creating and the excuses he gave was mostly about not being able to "live" from this game and having to work and not having much time to work on it.
At least I remember reading it somewhere a while back. I think these guys, when they start to create a game as an independant creator, they should make sure they have enough resources to finish the first game, then after finished they could put it on sale on steam and other plataforms to have enough to start funding the next alongside with patreon subscriptions.
Some of these guys are too used to create a chapter that you can play for 15 minutes and think people should already fund their work to keep going.