Is it possible for those in a given diocese or parish to ignore what the national church does? Can parishioners really say "Well, my parish isn't like that?"
The short answer, from experience, is (a limited) "yes."
I left ECUSA a long time ago, but my own observation is that most of those in the pews are simply unaware of what is happening outside their own parish. The, um, "church experience" is completely tied up wth the parish and there's generally little news or other information from outside coming in.
As a young teen I remember going with a group of my peers and a (liberal) mother to a memorial for Pike. I had no idea who Pike was, other than a he was a famous bishop who'd died...
It was something more than a decade after that when I was unavoidably faced (as delegate to diocesan convention) with the reality of my ECUSA diocese -- and subsequently discovered there is Anglican life outside of ECUSA.
There are many good people in ECUSA yet today --from laity to bishops-- they remain in my prayers because there are difficult and horrific days ahead of them.