Every bit is important. It’s not that high score subject tests give any blanket “advantage.” After all, the kid could have other issues. And this is holistic, not rack & stack. But the lack of subject (or AP) scores can mean an important piece in competitive decision making is missing. Any college that cherry picks will be looking at that whole.
They don’t guess, “Oh Susie must have gotten good scores, she has a 4.0.”