The discussion of "MD5 collision resistance is bad, but md5 preimage resistance is still ok, so using md5 for applications where preimage resistance is required

The discussion of "MD5 collision resistance is bad, but md5 preimage resistance is still ok, so using md5 for applications where preimage resistance is required is ok" is I think completely valid (however pointless it is) However for password hash functions to be useful they also need to have a high work factor to make brute forcing even more difficult.