The IETF is not the ones deciding how the English language works, especially not outside of their own specifications ;)

But, if we're using IETFs grammar:

"Should" here implies unless you have a good reason, you should do this. For anything related to open source (which is based on voluntary contributions and practices), that's a bad choice.

"May" would be a better pick here, to remove the assumed obligation to run office hours.

I can't imagine a more HN thing than someone referencing a technical specification to define the word 'should'.