That's debatable, really. People support a game developer for many different reasons. Getting updates is just one of them. Some people pay because they actually care for the dev and trust his word when he says he is struggling, others pay for the work he has already done so far, and others just don't even care since it's peanuts money for them. Of course, if you subscribe only because you are convinced by his promise of a future update, and you don't get that update, you have all the right to cancel your pledge and accuse him of 'false advertisement' or whatever, but even then you won't be really able to do anything else since Patreon model means that you are not buying a future work but supporting the creation and getting some perks in exchange, and he has indeed created something and his patrons receive what he promised on his tier list: access to his discord server, to his mind-drops, to his polls, and also to the game - when released. After all these months without a proper update, I honestly find it hard to understand why 3.4k people are still supporting him monthly, but that's just a testimony of the quality of the game and how he was able to build trust precisely by not taking people's money when he didn't deliver. He always sounded sincere and he did as he promised, so now there are a lot of people who are still willing to believe this is just a temporary block. And the fact is none of us can really prove he's being dishonest and not working on his game. So everyone has to judge by themselves if he's worth their money and act accordingly. And many people still think it's worth it, even when confronted with the same facts that lead other people to call him a milker and a fraud.
Everything is way more complex than people tend to express in this forum.