No. I argue paper files are more secure, at least they wouldnt be target of digital breach where millions' data could be "hacked"

Maybe your local dentist is like this, but almost all 'large-ish' hospitals are totally digital these days. The compliance rules for patient data safety and security are really crazy too, I would not be worried. That said, paper is in fact more secure in general, as it is very difficult to just 'grep' a filing cabinet, move several of them in a few seconds, or ransom-encrypt all of them before anyone notices.