Does the BadUSB issue also affect SD cards?
Solution 1:
To a point, it's safer. But sd cards are turning more into usb everyday.
Sd cards will still be vulnerable to having viruses on them, and a user clicking on the program to launch them. I don't see them being used as hid (human interface devices) yet, so you should be safe in that regard.
Having said that, what is your potential attack vector? Are you sharing the sd cards or usb flash drives with other people (strangers or known people, alike)? If you are the sole user and will maintain complete control of the flash drives, then I would not worry about it.