It kind of makes sense in-game, though. See, there's no such thing as a veteran Helldiver. The life of a Helldiver is a recruit who makes it through a short obstacle course, gets slammed into cold storage, and gets airdropped into near-certain death after the most recent meat puppet dies. On the outside chance that he's the one who manages to survive, he needs to have his emotions kept high long enough to spend his time improving the ship before getting launched into the next mission - and the first Helldiver in a mission never comes back. The propaganda needs to be a constant stream because basically no Helldiver survives more than about 30 minutes after thawing, and they need to keep his morale up.