Ubisoft are notorious for their DRM measures but they will slightly ease up with Watch Dogs Legion as players will not require an online connection at all times.
Singleplayer games should not be tied to internet connection by any stretch of the imagination but here we are - the fact that Ubisoft decided not to put this restraint on players is newsworthy. Yes, Watch Dogs Legion will not require an internet connection to enjoy the singleplayer portion of the game.
The first reason why this is important is quite obvious - when players go to remote places, they can still enjoy the game even if they don't have internet access. Alternatively, someone's connection may be temporarily unavailable and that will not prevent them from playing the game they paid for.
Microtransaction strategy is another important takeaway from that stems from this approach. Assassin's Creed Odyssey was generally well-received but the game was marred by the "time savers", in-game shop items that were designed to make players progress faster and get better gathering rates. Coupled with the egregiously sluggish portion of the game where the story progress slowed down to a crawl, it was obvious the game was designed to push these "timer saver" microtransactions.
Considering Legion will not require an internet connection, it is unlikely something along these lines will happen here as well.
The same AMA that yielded the information about being able to play offline noted that the only drawbacks will be the inability to see community photos, take in-game pictures and share them out. There is no mention of being unable to acquire any time-saving nonsense so that's definitely a win for the Legion experience in our book.