Was Guido right to hide the war to his son?

I think he was right to hide the war to his son of barely 7 years old. If not, his son would have been traumatized and he probably would not have survived being scared and everything and not understanding that the German wanted to exterminate Jews. Giosè, because of the game, was more than motivated to stay hidden to win the tank at the end.
Even though it wasn't Guido's fault, I disagree with his strategy for the simple reason that Dora, Giosè's mom, didn't know about the plan and could have mistakenly said something to Giosè. That is not a reason to not hide the war to his kid, though, it's just that it's something he didn't think of, and for that, Giosè could hold a grudge against him if ever he found out. Also, I don't think in real life the Nazis would have let that happen. What I mean is I don't think they would have been so blind and I think they would have noticed. Obviously, it's only a movie, but I think in real life he would have had more difficulty hiding Giosè.