...

If you don’t say C++, there’s no reason OMPI and MPICH can’t do the obvious, trivial and intelligent thing.

I guess I disagree with all three of those hyperbolic assertions. :-)

You're ignoring the long tail of consequences here -- what about PMPI/tools? What about other C++ features that we should be using, too? ...?

No scope creep. No slippery slope. Do the one thing we need to go and stop. Leave the rest for MPI-5. Jeff