Filesystems are close to being obsolete in the cloud. We still need them to get applications "started", but after that, applications shouldn't really be using a filesystem. I/O should take place with a remote (or local) service that deals with the many moving parts behind the thing the application really wants (look up some data, read some data, write some data, delete some data) in a large distributed system (logging, tracing, authn+z, storing/retrieving, sharing, archiving, etc). How it gets stored and on what media is pretty inconsequential to the app, and in many cases things are just more difficult because of the inherent limitations of storing data in files in filesystems on disks.

The other thing is, once disks are as fast as RAM, there's really no point in having RAM. It only exists because running programs would have been really slow if we had to wait for the disk to seek 100 times to print "Hello World".

Combine these two scenarios and you land smack into one new reality: all applications should be doing I/O in a giant pool of state that is both data storage and computational memory, as a global, distributed, virtual storage memory manager. In effect, clusters of computers should be sharing CPU and storage, and applications should run across all of those resources, like one big computer cut into 100 pieces. The idea of this was called SSI before, but it can actually become reality a lot easier if we can make the abstractions so simple that we don't have to code around ugly problems like threaded-shared-memory apps.

Basically we need to make a new "layer" that will allow us to delete a couple of old ones, and that simplicity will enable whole new designs and make currently-hard problems easy.