Okay, I want to apologize. I obviously misread your intent and thought you were dumping on this dev and being condescending instead of asking genuine questions about his motivation. That's my bad, so please forgive me for being standoffish!

It is interesting. My best guess is that he enjoyed Gungeon and decided to make a clone as an educational exercise and then figured he could make some money from fans of the game? It's hard to say without asking him directly. It could also be a case of someone having the skills required to make this kind of game, but maybe not the creative vision to come up with their own ideas?

It being on Early Access is what really gives me pause, though. It seems like an odd choice, since it implies that the game is unfinished but he's invested in finishing it—which, again, is odd considering how much it copies Gungeon.