This isn't surprising, but I guess the results need to be put into perspective with the use case for distributed file systems and NFS eg. reasonable scaling for static asset serving with excellent modularity, in particular when paired with node-local caches. Of course Ceph etc. won't scale to Google Search and Facebook levels, but it's still damn practical if you're scaling out from a single HTTP server to a load-balanced cluster of those without having to bring in whole new I/O infrastructures. And they help with cloud vendor lock-in as well; for example you can use CephFS on DO, OVH, and other providers.