They are interchangeable for citizenship, but a CRBA and a birth certificate tell us more than a passport does. In particular, a CRBA tells us that the source of citizenship is a statute, and that evidence has been presented and the claim to citizenship has been adjudicated in light of the statute. A passport doesn't tell us that.
Nonetheless the law makes it a legitimate substitute for the crba. It’s a fact. If I weren’t on my cell phone I’d look up the us government link for you.