The fact that other sites are able to do this, means that they are using the same weak encryption, or likely no encryption at all.
When a site restricts the max length of a password, or character types, it generally means that they are likely storing your passwords in some sql server completely unencrypted.
If a website is properly salting and encrypting your passwords, then they should have no way of determining what your password is. or even if 2 people on the site have the same password as proper encryption creates a new hash each time the came exact text is encrypted.
a billion people could have a password of 1234, and every single hash would be different.
For even more security, the salt can be stored on a separate server, though it is not a requirement, but a salt prevents a precomputed attack on a users password, as each user will have a different salt, thus they will be forced to brute force every single hash, and likely never crack any reasonably long and properly random password.
If a site is able to tell you your password, it means they are not securing your data. (if they can e-mail you your password, it is a red flag that they are not even encrypting your password.
if your bank does any of this, then switch banks.
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