$this->validator->getValidated() looks stupid and unnecessary

There could be many examples. One that comes to mind, is an address field. Validating address fields is only asking for trouble...

No, it has max length. At least it should be checked.

If the address is longer than your column length, you cannot save it to the database.
If it is too long, e.g., more than 1,000 characters, it must be invalid.

If it has invisible characters, it also is probably invalid.
If you expect English alphabets and 1-9 numbers, Chinese characters are invalid.

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