Markle became the meeting's lone holdout over the issue and eventually left the meeting. They like to believe that diversity is their strength so they can incorporate divergent points of view, but that is premised on the belief in the system itself which Don lacked. Don believed an open mind was an invitation to sin so he did not try to incorporate other ideas. That seems to be the attitude of the mainstream church at large. New ideas, new ways of seeing God's kingdom and welcoming others into it, are taboo.
Some churches drug their heels.
The Southern Baptist denomination was largely formed as a way to come up with a religious defense of slavery. On the other hand, the Quakers were running underground railroads and were ahead on abolition. You're going to see that all over again. Denominations will split over this issue, but they are all moving slowly in the direction of more inclusion.