v3 consent to attribute release : required vs optional attrs ?

[Tom Zeller]

I have not done my homework, but does metadata provide whether or not
a requested attribute is required or optional ?

More to the point, if an attribute is required by a requester, should
the user still be allowed to exclude it ? I would think so, but with a
caveat that things might not work properly, I guess. Maybe this is
another configuration toggle.

Probably out-of-scope at the moment, but I'm trying to wrap my head
around the flow.