Agents will send players to where they will earn the most commission.Agents and players want to go to where they will play. For players around 18-23 it's probably the number one thing they look for because it's the number one thing that correlates to career success
A reputation for not playing youth will be a big blocker for signing youth.
Without checking I would guess there are a lot more players over 23 than under 23 playing in the PL.
Getting game time under 23's isn't the main thing for agents at this point.