Ok so you can replace the scopes in seconds... but can that be done inside the tank or do you have to get out and fix it in real life? Did these replacements occur on the fly in the middle of the battle and if so, how many replacements did they have in the tank?
As well, I was leaning more towards the regular view ports and not the scopes.
From what I seen in the animation in the T34, your head moves to the left viewport in the hatch, not a scope. While I imagine there was a scope, it doesn't appear to be used based on the animation provided. And besides that, in the german tanks that use scopes, you have a blacked out scope texture applied or a full screen view of the scope..... in the russian tanks, you're looking through the viewport.
German Example:
How quick was it to change this glass in the middle of the battle?
It may not be needed for the tank crew, but I think the soldiers being run over and shot at by tanks with invincible glass that is never obstructed wouldn't mind this feature in the game..... esspecially those who are stuck with rifleman classes and have no way of taking out a tank except perhaps trying to screw up it's vision and make a run for it.
And if it forces the driver to pop their head out to see where they're going or be stuck listening to the tank commander on where to go, then so much the better.... it's probably make drivers a bit more cautious and listen to their crew more often.