Yeah, Ubisoft's games pale dramatically when you've played GTA 5. Where Ubisoft's primary design principle is to litter their games with collectibles to keep you distracted, GTA 5 keeps you distracted with its good design, emergent situations, and large amount of interesting and fun missions. You actually have to go out of your way to even enable any of the collectibles here, and even then they aren't trying to distract you or get in the way of other things, whereas Ubisoft keeps dangling them in front of your face to keep you busy (and to reduce the risk of you trading in the game during the vital first few weeks after release).
It's also amazing how natural GTA 5's world feels. Even Ubisoft's most beautiful games come off as artificial and constructed, while GTA 5 feels like an actual world people could live in. Every single part of the world feels lovingly handcrafted, and there's no sign of copied and pasted content.
I'm growing increasingly tired of games, across all genres, that try to save themselves work by using layers upon layers of collectibles to pretend like they have content, when the actual campaign would otherwise have taken only a couple of hours to complete. GTA 5 is filled to the brim with actual content, and doesn't need to pretend.