You have to understand how dumb this take is.
QR scanning PSBTs just ingest data, your HWW still has to show you the relevant details of your transaction legibly.
Which they all do/did.
Discussion
SD card PSBT management is not as secure as QR.
To make it the same security you would need to use a new SD card for every signed transaction.
So what did they do?! They worked on the MK4 with NFC.
NFC isn't as secure, nor is it as useful as QR signing.
Another benefit of QR based HWWs is address verifications, which you can do much easier.