Why do we keep letting are youth go to real?

Now I understand it isn’t exactly the club’s choice but the player’s but for what, 4 consecutive summers we have one of our most talented youth players Gabriel Suarez leave, before that we had Ramos, someone who led our youth scoring 33 goals the year he left and he simply leaves to our biggest rivals? It feels like kick to the ankle, targeting the base, the core to weaken the club because it weakens us majorly