Having learned decades ago when iron sights were the norm, I would advise you to just focus on learning how to shoot with the scope and forget about iron sights.
Advantage of iron sights: cheap, reliable. Disadvantages: poor definition, non instinctive (you have to look at the sights rather than your target). Advantages of scopes: instinctive (you look at your target and the crosshairs are in focus), better clarity, better visibility. Disadvantage of scopes: fragile, rifle movement more visible than irons (the rifle really moves the same amount with a scope, you can just see it better). Winner IMO: scope.
Never try to educate someone who resists knowledge at all costs.
But what do I know?