This is a very solid point. We already had an open cryptographic competition to select a password hashing standard, and we have a winner: Argon2 is being developed as a new standardised password hash (i.e. slow-hash).
If you're going to introduce a new one, it should go through at least the same level of cryptanalytic scrutiny before anyone uses it.
If you're going to introduce a new one, it should go through at least the same level of cryptanalytic scrutiny before anyone uses it.