I don’t believe it is a bug.
The only attribute of the data in a bound form that is supposed to be normalized to the proper type is cleaned_data. All data submitted (bound) to the form coming from the client must be strings. Form POST data doesn’t have any other type. Note that POST data doesn’t quote strings, it’s submitted as name=value. When Django receives it, it can’t do anything other than accept it as a string.
(And yes, I did read your submitted ticket.)