Very simple. I NEVER want to flag PvP.
Ever.
If that means I can't buff or rez someone who was inconsiderate enough to try to quest with me while flagged, so be it. I'm all for having that be switchable.
That won't ever change.
My friends don't PvP either though, so that's not even going to be an issue.
I will NEVER be OK with someone else deciding for me that I should PvP.