That doesn't fix the issue though. The issue is a killer USB or a virus on the disk. Being able to only read an infected file still allows it to be read.
Also, this is only a software solution as the USB protocol would require bidirectional transmission.
But it would bring us back to being as safe as a CD or diskette was.
I was thinking a special chip, talking bidirectionally both ways, pretending to be a PC host to the USB drive, and pretending to a DVD-ROM to the actual PC.
Also, this is only a software solution as the USB protocol would require bidirectional transmission.