Is A Bigger Game World Better?
Ghost Recon Wildlands is the perfect example of this. The self proclaimed king in term of it's size, at 1000 square kilometers, the world is ultimately empty. The inside of buildings are simple, carbon copies, of each other. The only reason why one would want to explore this world is to find all the weapons or complete the repetitive quest line. Ubisoft would of benefited in creating a smaller, more dense, and unique world.
Another great example is the Just Cause series. Here, again, we have a massive world with an excessive amount of recycled assets. Enemy camps have a lot of same "big red buildings" just begging to be blown to bits. The first time you blow them up is quite fun, the second time is okay ... after that, you're pretty much just doing it to complete the game.
This is not to say that they are bad games. I have played and enjoyed both of the above series extensively but it certainly wasn't due to their world. Yes, they were big (as advertised) - just not interesting in itself.
The open world genre is meant to be a sandbox for the player. Here's a world, here are your toys now go have fun. The game fails when players have to be enticed, either through quests or item pickup gimmicks, in order to explore the world fully. Make the world smaller and more interesting instead of bigger and bland.
There's an interesting video here that compares the map size of popular games. Which game world ended disappointing you?