I strongly agree with this. I have volumes on my file servers where I very strongly wish I could disable POSIX permissions entirely, replacing them with an inherited ACL from a file system root or subdirectory root.
I want to be able to say "Absolutely all files within this tree must always have the permissions <x>, don't make me waste my time with badly behaved programs that set stupid umasks, idiotic network access clients, etc. Just MAKE IT SO."
The only issue I see with this patch is that it's done at the file system level, and IMO this is something that'd be useful for subtrees within a file system too.
I hate to say it, but what I want is to turn off UNIX-style permissions for some directory trees and have Windows-style inherited ACLs instead. Right now I can have the ACLs, but the permissions triplets always take priority, so some stupid @#$#@W app that sets mode 0700 every directory it creates (I'm looking at you, Thunderbird) still breaks access for everyone else. What I want is for the FS to completely ignore permissions within those trees or force them to a specified value on file/directory creation.