I'm criticizing the shallowness and lack of information in the comment. Everyone knows games should be fun. Saying "[the game] needs to be fun" has literally 0 bits of information and is a lazy explanation for why games don't succeed.
art has to risk failure or it’s not art. perhaps has to even be near certain to fail.
no one should be depending on art to feed their family.
no one should be making art for any reason other than love.
art must be beautiful.
as many have pointed out, blockbuster movies and triple a games are interesting, but they are not art.
So "the game isn't fun" needs a lot more context on who is saying it, and is useless otherwise. Do they like your genre? Are they miscommunicating what sounds like a game design issue when it could be an art/sound issue? Did they just grab your game in a bundle/gamepass and weren't really in the mood to play your game?
It's all speculation. And it's probably better to find better feedback than try to psycho-analyze every comment that way.
I mean, why do people want to write buggy software? It's not on purpose, they're just not good enough to deliver quality in a timely fashion.
My experience with most indie games cannot deliver on a core gameplay loop that's satisfying, even when that loop is not the draw of the game in which case I'd expect them to ape something competent.
IMO an example of a studio that doesn't mess this up is Giant Games. I've liked some titles more or less but the core gameplay loop has always been competently designed.