That’s some survivorship bias shit right here. I can’t tell you how many shitty, buggy games I played in the days of early console and PC gaming. Even games that were revolutionary and objectively good games sometimes had game-breaking bugs, but often it was harder to find them without the internet.
Plus, don’t you remember expansion packs? That was the original form of DLC.
Especially when KSP has had such an active and vibrant community for a decade