People like to scream that Denuvo is always online, but it's really not. I've been able to get into Denuvo-using games in offline mode fine, I just don't think you can do that indefinitely , however. Unless you actively decide to go off the grid, have the worst internet imaginable, or are on deployment in the military or whatever... you're unlikely to ever be inconvenienced by Denuvo having to check-in with an internet connection occasionally.
Harder DRM (Denuvo) on top of softer DRM (Steam) is a bit silly, but people work themselves into contortions over Denuvo as a bogeyman. First it allegedly destroyed SSDs (disproved since), now it causes performance issues (I believe tests have shown it hampers performance by... a few frames at best?).
There's a hilarious case on the Steam forums right now, with someone whining in every thread about how Denuvo is SEGA treating paying customers like pirates. Some brave soul raked over that user's posting history and found... admissions of piracy.
A lot of Denuvo whining is projection, and propaganda.