I swear at this point they do this shit on purpose. Poorly implement vehicle models into the game, their suffering-oriented game design makes people mad enough to want the vehicles better represented, but they don't accept any other "secondary sources" so people resort to leaking classified documents.... It's too crazy not to think it's on purpose.
Plenty of the "classified" documents aren't actually classified. Oftentimes it's a case like this, but I remember one person posted a link to the Wikipedia page for a WW2 tank to show how the in-game stats were nerfed compared to the actual vehicle, and they said they couldn't use data from classified documents.