Dude, it's not locked behind a paywall. It's still a preview of the new version, i.e. unfinished, so Patreon supporters, who help keep this game free for the rest of us, get to test it early to find anything else that might have been broken before the finalized 0.3 gets released to the public. It's not shady, it's literally just doing what everyone else does that can't just make these games entirely for free on their own time out of the goodness of their hearts. Either support the developer or be patient and wait.