Just because a particular organisation doesn't have a ton of young people clamoring for a pulpit doesn't mean God isn't calling people.

Since when did God decide to limit his call to teenagers barely out of diapers anyway?

How old were the apostles when they were called?

Jesus Himself did not begin to preach until He was about 30 years old - and He was considered a "whippersnapper" by the folks in His day...