"Pay Wall" isn't a grey term, it's a term that refers to a something that blocks people from content unless they pay. He produced this game for FREE before he had Patreon/Subscribestar (when it was still a mod) and continues to be FREE.AAA gaming has seen a recent trend of "paywalling" early access to games behind a $10 deluxe edition upgrade. Zip is doing the same thing, but with no game in the end.
Maybe this is a difference in opinion on the definition of "paywall." But he has offered a product, told people those who subscribe to his service will get early access to that product, lied about the development and pending release of that product, and scammed people out of their money. That is my complaint regardless of what definition of "paywall" is settled on.
Nobody has ever needed to be a supporter on any level to get access to this game.