The title pretty much sums things up, with patch 1.04 for PC released yesterday, Control has had DRM added to it.
Of course there was no information about this being added anywhere when the update was released.
If you attempt to run the game executable directly, now before the main menu it pops up a message stating you must launch the game via the Epic Games Launcher and have a valid Epic Games User Account, which means the game also no longer works with the launcher in offline mode.
Because of this change Steam Controller support has also been broken.
Who knows if Epic, Remedy or 505 Games are responsible for this change, but either way I certainly will not be getting any expansion DLC for it now unless this is reverted.
If you want to continue to be able to play offline or use a Steam Controller, do not update to the latest patch.