He knowingly "released" a very slightly incomplete version with a couple of bugs to thank his Patrons for their patience and support while he revisits the last few pieces that needed addressing. It wasn't intended for public consumption and he asked that nobody leak it for exactly that reason. That somebody decided to ignore his wishes and leak it anyway reflects more poorly on the leaker than it does the dev, IMO.
I bought the game on Steam originally, and I subscribed to his Patreon the last couple of months as the update started getting closer. I pay to play it because I think the story and renders are great and I want to encourage and invest in the dev's further growth and product development. So, thank you, but I don't want or need your pity.
And I, personally, do not see it as a slap in the face at all, because 1) I have enough empathy to understand that I know nothing about what the dev may or may not be dealing with that affects his work, 2) I have enough common sense to not hold this or any other dev to some mythical standard of project development that only serves my personal whims and desires, and 3) I have enough other things going on in my life that I don't feel the need to go out of my way to shit on people who are using their own time, energy, and resources in order to create something for my enjoyment.
