I think it could be beneficial for players, if having a passionate developer able to spend more time working on it allows them to make future evolutions significantly better than they could be in a world where the developer only has time to work on it passively. That said, I am generally a proponent of indie game developers being paid for their work, as an indie game developer myself, so my personal bias may certainly leaking be leaking into my evaluation :)

I'd note it also doesn't need to be done in a way that deprives players of any free future evolution. Paradox has a nice model for their games where they release expansion packs, where about half the content is part of a free update to the base game and half the content is paid. That would be perfectly suited for a case like this.