I googled "membership in the Boy Scouts of America numbers graph" to get the other. It's the fourth image.
I can't absolutely vouch for the data and couldn't get to the page the second graph came from and don't have a chart for the most recent years, but my understanding is the membership in the BSA was in decline for a long time. The small rally around 1998-1999 was a surprise though.
In summary, the BSA’s recent move hasn’t mattered for its’ decline, in part because those who complained were not interested in having their kids in there in the first place.