+1 from me too - since classic confinement is already an option and as a strict mode snap with password-manager-service auto-connected has no additional authority than a classic snap this is just a stepping-stone on the way to classic confinement.
Although I wonder - since it has been ~6 months since classic was granted and there is still no classic snap published, is classic still definitely required for this snap? If users are happily using it without classic perhaps it is fine as a strict-mode snap and so in that case I do not agree that password-manager-service should be auto-connected.