I think tasking the IESG to look at how to reduce the time commitment
would be an incredibly good idea. I'd feel a lot more comfortable with
the community giving the IESG clear guidance that we'd like them to
solve that problem than with the community trying to come up with the
solution.
That said, note that there are a number of AD candidates who do take
explicit advantage of the full-time nature of the job. They get
involved in IETF tools development, coordination between the IETF and
other organizations, process reform, unstucking major issues that need
to be unstuck.
That's all great, but it does all take time.
I'd like to live in an IETF where we have room for people who do want
to spend a lot of time on all those issues as well as a place where ADs
can take responsibility for the technical work in their area and
minimize time commitments.
I think the balance between personal review and trusting others is
something that will shift both for individual ADs and over time. I'd
hate to see the community over-constrain that.