Yea, that is a big caveat to ZeroFS. Single point of failure. It is like saying I can write a faster etcd by only having a single node. Sure, that is possible, but the hard part of distributed systems is the coordination, and coordination always makes performance worse.

I personally have went with Ceph for distributed storage. I personally have a lot more confidence in Ceph over JuiceFS and ZeroFS, but realize building and running a ceph cluster is more complex, but with that complexity you get much cheaper S3, block storage, and cephfs.