How Do I Back Up My Photos After Leaving Google?
A folder of dateless files is not an archive. Here is what to fix before you call it a backup.
Before you think about where to put the backup, make sure what you are backing up is worth keeping.
A folder where every photo says today, with thousands of .json files nobody will ever open, is not an archive. It is a problem you have postponed. In five years, when you plug that drive in, there will be no way to tell when anything was taken, and the odds you run the merge then rather than now are not good.
An archive works when each file carries its own story: the date, the time and the place living inside the photo, not in a companion file that any copy can separate from it.
So fix first, then copy. The app writes everything into the photos themselves and can sort the result into year and month folders on the way out, then send it straight to a USB drive. What you put away is a library any computer will read correctly, now or in a decade. The first 500 photos are free.