This entire thread makes me sad.

What you're talking about here is not architecture.  It's a science
experiment.  Everything you talk about that customers have trouble with,
"An object that spans multiple zones", "What if zones aren't powers of
two" ...  these are all problems that filesystems are supposed to solve!
The problem is that you don't have a filesystem on top of your block
devices.

I think having a BOF on zoned storage is a horribly bad idea because it
means you're only going to be talking to each other, reinforcing this
stupid wrong direction that you're heading in.  You need to be talking
to filesystem people to figure out how to hide your terrible API from
applications.