If players had something in their contract to say "Will only play maximum 30 league games" or "Will only play in q/final round and beyond" the clubs will have no choice. Some will say "but then clubs won't sign the player" but if a player like Rodri complains about how many games he plays - do you think Manchester City would sell him because he cannot play in the League Cup or FA Cup 3rd Round? If the top players do it, the rest will follow and young players might have more chances to play.