Call of Duty Tease?

This video (NSFW) shows a mysterious message that's been appearing in Call of Duty: Warzone. Some battle royale combatants have had the words "know your history" pop up on the screen. It's not clear what this means, but many, including VGC (where we saw this) seem to think it's a tease for the next installment in the main Call of Duty series. A recent logo leak suggests this will be called Call of Duty: Black Ops Cold War, and if speculation about this new tease is correct, we may be hearing more about this soon.