Not sure when this happened but this did not used to happen. I hadn't played DCS in a while and just launched it earlier this week. I noticed some updates were installed.
But now my PC's monitor goes to sleep 10min into the game (that's how long I have the "turn off display" setting set to). I have to wake the display by hitting a key or moving the mouse.
And just to be sure this isn't an issue with my PC, I launched other games (even some with HOTAS support) and noticed those did not allow the display to go to sleep; so this is a DCS World issue.
I found this thread that sounds like the issue I'm having, but it is from 2014 and has no answers: http://forums.eagle.ru/showthread.php?t=159736
I know I can simply disable the "turn off display after X time" setting, but I rather DCS World did the correct thing.