I think Burnout Paradise almost got it right (bare with me, as this may not come out how I intend).
A large open world can be fine, although I prefer the idea of smaller districts fully fleshed out with tons of detail (Yakuza), these can even be linked together via a larger open world if you want a sense of scale. The issue I think comes from structure, with too much to do at any one time.
Burnout Paradise sort of overcomes that with the license based progression and the Big Suff Island add on. This can be worked into an open world game in a much better way
Say for example your charaxter is doing a story arc when their partner / friend / child / dog / breakfast is in grave danger. The particular arc may be 3-4 hours worth of content. Don't throw in cookie cutter side missions and discoveries that take away from that....
What's that? You child has been kidknapped and time is of the essence? I'll get to it, after I have been to the shops for Doris that old lady I met 10 minutes ago, to get her some cat food for her husband. It makes no contextual sense and just gets in the way. Have relevant side quests that work in context and only for that arc.
If between arcs, then open up everything, but close them off for the next story arc and so on.
It makes everything feel relevant during the main part of the game and then open it up after that has finished. You could even create additional stories after the fact in the same world (see GTA IV expansions, Fallout 3, etc). I don't want to be travelling from one side of a huge map, to the other side for a pointless fetch quest, it breaks the immersion of the game and makes me not care as much for the chracters involved.
As good as the Witcher 3 was, it soon became apparent that even there it descended into cookie cutter quests to fill a map, just with some better smoke and mirrors.