That wouldn't be at all surprising, no. Floppy disks were all but gone by the turn of the century. People born after 9/11, who will never have encountered floppy disks, are in their mid-20s and having their own kids by now.

I saw only one size of floppy disks in my life and I'm 35.

I mean.. no?

8"

5 1/4"

3 1/2"

and a couple less standard ones, then you get into sectoring (hard, soft), sidedness and density, plus disk formats on top of that

This list is wild: https://en.wikipedia.org/wiki/List_of_floppy_disk_formats

proprietary zip and later jaz drives as well

Hah I still have some Zip disks sitting in a drawer, completely unreadable

i don't think that's the type of knowledge you can expect fron even contenporary non-technical readers