That isn't really accurate though. It is just a bit of a hot take without any real substance.
The best club in Scotland have had Tierney, McGregor, Bain, Forrest, Johnston all playing pretty regular in recent times (add in donkeys like Hendry, Morgan and Ralston and they have given Scottish players plenty chances). Griffiths would have been too had he not had his troubles. If they are good enough teams will play them - we simply aren't producing enough good players.