Apple says APFS is the default file system, but does that mean one
must install APFS or will there be the option to retain HFS+?
Waddya think?
It's always a bit dicey to try to predict Apple; they have a long history of zigging when folks thought they would zag.
However, my belief, based on High Sierra betas, is that APFS will not be mandatory in High Sierra--you can keep your drives formatted HFS+ if you want.
There will likely come a time when that changes, of course.
