Totally agree. I think the only real issue here is expectations. If the project mentioned was crowdfunded specifically and only with the goal to deliver a game, then I think people would be right to be a little bit irked that the developer is instead tinkering with their own programming language rather than the game, after eight full years. However if the project was funded with the understanding that the developer was just going to explore and share the process of game development and everyone is on board with them going off-piste to develop something interesting, then I guess that's fine.
That said, the amount of money in question is $67k spread over 1660 backers (~$40 each) so it's not like this person has grifted millions then done a rug-pull :)