Funnily enough, "the end of time" for NFSv3 is in about 15-83 years, depending on whether the implementation uses signed or unsigned 32-bit integers for timestamps: https://lwn.net/Articles/717076/

True, but I define end of time as a 32-bit integer number of seconds from 1970.

The only sensible interpretation frfr

Version 4 has been implemented in and widely used in Linux, FreeBSD, Solaris, Microsoft Windows...

I'm not sure what value of "much adoption" you're using, but I think it's had great adoption.

It's widely implemented but not adopted. Most vendors implemented v4 to tick a box for some RFQ. I don't think any of the commercial fileserver vendors publish numbers but I used to work in that space and internally customer adoption of v4 was always a single digit percent. When I was on the customer side in HPC none of the supercomputer clusters were using v4 (I'm sure there are exceptions that I wasn't aware of).

I use it all the time. It's a huge improvement over NFSv3 for many reasons (performance, network ports, locking, ACLs, ...).

All the operating systems I names have fully implemented and mature NFSv4 stacks. Definitely not a MVP to tick a box.

That’s completely incorrect. NFSv4 was a quantum leap in performance; greatly reducing network traffic via COMPOUND and dramatically improving write performance via delegation.

All my file access is over NFSv4 (in a mix of 10 GbE and 100 GbE).

Having GP’s crate expand to support NFSv4 would be welcome but a nontrivial bit of work.