Ubisoft just added Denuvo to Assassins Creed Mirage via a day-1 patch a few minutes ago. AFTER all the major reviews went online.

I'm not following closely and haven't gamed on PC in a while but:

Denovo is a technology that is supposed to prevent copying games (DRM). Not sure what it's current state is or might be mixing it up with other DRM, but DRM is known for causing headaches for paying customers. Using excessive system resources, refusal to launch for legitimate paying customers, spyware/excessive data collected and sent to a corporation, etc. In some games, volunteers will patch bugs out of a game, and this will cause the game to think it's cracked and refuse to launch.

Some DRM is "phone home" and can't be played offline, so people in remote areas can't play. And sometimes the company doesn't want to keep servers online when the game has been out for 10 years, so people that purchased the game can no longer play.

In this case, the company let reviewers rate the game and got the initial scores and sales, then pushed the unpopular DRM update. It's scummy. If you're using it, then use it. Don't bait and switch.