This is really helpful, thank you!
I never understood why the shareable /usr is parent to the non shareable /usr/local. Wouldn't a /usr/shared be way easier especially in the early network days?
If anyone has a link or some insights into this historical nitbit I'd highly appreciate it!
But when I mount a shared /usr on a remote machine it will always have the mount point /usr/local as empty folder - and either have an empty folder or have a mount target that is dependent on a network resource - that's why for me it's so unintuitive.
But then again I started with network stuff way more than a decade after all this got created 🤣