So what happens when that kid earns his Eagle, grows up and wants to be a Scout Master? Open door...
That's a fair question. In a perfect world the old policy was better. That said, at a young age, IMO, it's way too early to be able to accurately enforce a no homosexual policy. Many kids may not know or may be confused, or whatever the case may be with individuals. With the rule, it's almost a don't ask, don't tell sort of scenario because kids may not be at the point where they like boys or girls when they begin as Cub scouts and transition to boy scouts.
I understand the change in that rule to placate all the corporate supporters, etc. As other said, once you open the door it's a slippery slope, which is what we see here. Give an inch, and the left will go for the mile. As I said, the old rule was idea, but the pressure to change was pretty significant.
Your question is a fair one. If part of the agreement to be a Scout Master is to weed out homosexuals, I don't know how that could work in today's messed up world. It used to be part of the deal if you joined the military, but the fact that that's gone by the wayside would make it difficult here.
Bottom line is we live in a collapsing society now dominated by the gay issue. It's happened fast...too fast to handle appropriately because the left wing pressure will move at warp speed once they've decided to attack.