An interesting side point relevant to the article: the original intent of Multics was that pages would be the basic data structure, with the filesystem essentially merely a way to keep track of groups of pages when they were not otherwise in use or when a way was needed to refer to them. (The actual initial implementation fell short of this ideal.)
Don't use a _normal_ filesystem for large distributed systems.
Being able to seek() on a file (without having to download it first) is something that is very underrated these days
just like databases, clustered filesystems also conform to CAP. You need to pick which part of the triangle you need.
I really like GPFS, as it has lots and lots of hooks (like S3) for events. It also has "HSM" which allows you to optimise which part of CAP you want based on arbitrary parameters (for example I've seen a rule that was if the file was an image, larger than 1000pixels and red, put it on long term storage.)
Instead of being like databases, I like to think filesystems (clustered or not) as one type of database. Of course that is just more of a mental trick rather than any deep insight to anything.
CRUD has been around forever. Like literally, since the mainframes.