Not all, but certainly most families looking to adopt are looking for a younger child. I would guess that these children are older than what most families are looking for. After all, we already have a large population of teens and tweens in foster care.
We adopted a 3 1/2 year old. Challenge. We also fostered a 7 year old who was abandoned here by her Mexican family. Her mother was still in Mexico and wanted her back. We got her there. That also was a challenge. I would foster a child or two but adoption is a huge commitment.