I’m not 100% certain on this, but when I read the Parler TOS, I believe it indicated they DO NOT store the actual image of your driver’s license (front & back, which for whatever bizarre reason was required to sign up and open an account). Instead, they store a computed/hashed value of the image, which cannot be reverse-engineered to reproduce the original images.
That said, the requirement to upload real id is what gave me enough pause to never sign up..and far as I can tell, Gab does not appear to have any similar requirement - at least at the moment.
My two cents for all:
Never send a copy of a driver’s license over the Internet, except by a secure portal to a well-established bank. When you send the copy, that copy itself, should have your having placed a broad “X” across your face, in order to frustrate anybody who might use your likeness re that document.
Never click on a link in an e-mail message. Instead, copy the link and paste it yourself, into the URL address field of a trustworthy Internet browser.
What is all this about drivers license images to sign up for Parler? I never had to do that.