My understanding was most of the US members were against the changes. There were more churches with smaller, declining membership that were for it. I believe the UMC will survive on the exit payments, old member donations, and real estate sales for a while, but then decline into irrelevancy.
That could very well be the long-run outcome.
It will take several years for the UMC/GMC churches to sort themselves out and stabilize their membership.
I do not have a crystal ball and cannot predict the future, but, HST, you are right that the UMC is rich! The Florida Conference is keeping ALL of their real estate holdings.
AFAIK, GMC is not getting any of the Florida UMC real estate; each church is being allowed to keep and get title to its own property.
How the UMC vs the GMC fare in the future will be interesting to watch