Hi! Publisher here.
I'd like to offer a different perspective. The creator of the game, Mosu, didn't charge when they released the game on itch, despite the game's success and popularity.
Now, we agree in hindsight that the game should have remained free on itch. The Steam port, however, required money because it needed to have access to Steam's input API for controller support, creating Steam achievements, Steam trading cards, and more. We handled that for Mosu, and do not expect any money from them for this, not to mention languages.
We felt it was fair to charge $4 to $5 for the game on Steam because, as a publisher, we feel that Mosu deserves financial compensation for their game, but beyond that, it is potential revenue that they can put into their next game because, in my opinion, Mosu is a generational developer and their work should not only be creatively supported, but financially.
It comes off as completely unfair to me that Mosu is getting pushback for agreeing to release their game on Steam for under $5 while there are companies out there charging double, usually triple, the price for skins and lottery cosmetics.
P.S. We're likely going to be discounting the game to like, $2 soon.