It’s really simple… it’s difficult to keep things secret when an entire country is suddenly involved in a war that’s literally on it’s doorstep. It’s the same reason so many people in the US still don’t have the foggiest clue what the US actually did in Vietnam, Laos and Cambodia - it’s much easier to keep secrets when the war is happening somewhere else. So yes… despite what western historians will have you believe, the Soviet Union of 1942 did have typewriters - lots and lots of them, as well as people to operate them. The massive losses the USSR suffered couldn’t be kept a secret - by 1942, the Soviet Union was literally filled with millions of first-hand witnesses. Stalin also didn’t have to lie to keep people in the Soviet Union fighting - the true nature of the genocidal Nazi colonialist program (Operation Barbarossa was no mere military operation) was pretty damn self-evident by that stage, too. If you read actual accounts of people who witnessed it all you get a far better understanding of it than the hot garbage alt-history Enemy At The Gates is based on - I recommend https://oceanofpdf.com/authors/svetlana-alexievich/pdf-epub-the-unwomanly-face-of-war-an-oral-history-of-women-in-world-war-ii-download-28426547194/?id=001884036892