Like I said, Open world, has become a broader term than rpg, of what it envelops( considering gameplay).
In terms of authenticity, PB worlds do not have a fraction of detail as worlds in Assassin's Creed( Yep, that is true…Ubisoft has phenomenal world designers and artists, their problems come from other sources), L.A Noire/all Rockstar games, Witcher I/III, Mafia series, etc.
In terms of richness of lore( tied to exploration) and variety of locales, even less compared to something like TES series.
In terms of world activities, same is compared to Rockstar ( or Saints Row) games( which are almost unknown entity here).
The same is true with world interaction/physics next to Zelda, emergent gameplay next to Far Cry's, traversal next to Just Cause/Mad Max…and there are more and more and more examples.
I've played all the games you mention, and with the exception of TES and The Witcher series, none of those game worlds were close to being as immersive as PB's titles to me.