Disclaimer: This is all in MY OPINION. Other people will of course think differently.
I personally think that how original a story is shouldn't dictate how good it is. A story can have amazing quality, yet just because it isn't really "original" shouldn't mean it should be classified as "bad".
I also think writers stress themselves out too much about how original a story is. They, including me, always keep trying to make something original and unique, and end up making something that's usually rushed or just way too "out there" in an attempt to do that.
Practically everything has been done before, so I think everyone should stop stressing about the originality and stress more on the actual quality, but of course that's just me