Properly stored nuclear material is safe as well. But it’s still hazardous material because if the storage or handling are imperfect, they are harmful.
Passwords are the same, except we’re constantly finding new attacks and weaknesses.
As some examples:
1. When a new attacks is found against a hash construction so all the password stored based on that are now more vulnerable
2. When it turns out your auth server is logging passwords in plaintext so it doesn’t help that your DB is storing them properly hashed.
3. When your auth call isn’t properly validating hashed passwords so attackers can either bypass the correct flow or intuit things about the password
2. and 3. have again nothing to do with the question. Plaintext passwords are obviously unsafe material, but that's not the point of the question.
Nuclear material that leaks its containment is bad no matter what, how is a hashed password leaking a bad thing is the entire question and you're only addressing it in 1. but I don't find that convincing. When was the last time a practical attack was found on a hashing scheme that wasn't already obsolete 15 years ago?
Passwords are the same, except we’re constantly finding new attacks and weaknesses.
As some examples:
1. When a new attacks is found against a hash construction so all the password stored based on that are now more vulnerable
2. When it turns out your auth server is logging passwords in plaintext so it doesn’t help that your DB is storing them properly hashed.
3. When your auth call isn’t properly validating hashed passwords so attackers can either bypass the correct flow or intuit things about the password