In a decade, membership will probably be south of one million, about half of what it is now. However, the bureaucrats who run the BSA will have access to corporate largess that will in turn allow them to enjoy big salaries. As membership declines, the organization will sell off campgrounds that are no longer needed.
What will happen to the BSA is what has happened to the liberal, mainline Protestant denominations. When liberals take over, conservatives leave. An example is the Presbyterian Church, USA, with 1.7 million members in 2014, down from 2.5 million at the beginning of the century.
Good analysis. Makes no difference to them that nobody much attends their so-called services. Their endowments go a lot farther that way, and hardly anyone questions what's happening to the money/property.