Bruh it's only $2.99, practically free. He literally clarified why he couldn't launch the identical game version on itch.io.
He has certain tools on steam so he has to delay the itch.io to work on that plus multiplayer will only work on steam from what I'm assuming off reading his post, this just makes the itch.io purchase worthless my guy every future update will be met with a delay on itch.io plus won't include multiplayer (possibly) this just gives itch.io a bad rep and a waste of our money when we can just wait for the steam version every time we see a game on itch.io that supports many indie devs even if we do support those indie devs and we end up getting a lack of content and delays, then there's no point in buying from itch.io.
A lot of these supporters are students or someone who's not so gifted financially where every dollar matters, so saying it's only this and that is just invalidating. Also, even if it's low price, the money is not the issue, respect is more so the issue. We supported this early in development and somehow we're experiencing the inferior version, even in the future with the lack of multiplayer, achievements and such. It's like a slap to the face in return for early support.