I tend to agree with the reviewer on this one. The way CDPR advertised the game made it look like Skyrim, when in reality it is more like DA:I, but bigger. When Bioware advertised DA:I, they didn't promise open world, but huge zones open world-like
If you've spent long enough time in the Creation Kit for Skyrim, it ends up not feeling like an open world filled with things anymore. You begin to see each location as a separate cell. Outside the cell in the Creation Kit is nothing, just black.
Everytime you want to adventure into a cave, tomb, town, house or whatever you need to load a new zone, a new cell.
So if we go by your gogmeister777 words, then Skyrim isn't actually a open world, but technically is just a world with
100's of smaller areas which have to load.
PS: With Dragonborn for Skyrim came a new island named Solstheim which requires loading screen to enter.
Then in Solstheim there is more loading screens for each house, cave, dungeon and whatever you want to adventure in.
The Witcher 3 is like the real world, you have Europe, Asia, Africa. You can explore each of the continents without loading screen, but if you want to go to Asia from Europe, you need to load one time. That's it.