In password security, the longer the better. With a password manager, using more than 24 characters is simple. Unless, of course, the secure password is not accepted due to its length. (In this case, through STOVE.)
Possibly indicating cleartext storage of a limited field (which is an absolute no-go), or suboptimal or lacking security practices.
If the server hashes a hash, the plaintext password’s length is still irrelevant
That’s not true. There’s limits everywhere.
At no point the server has to deal with the length of the plaintext