Prophecies felt more open world than Factions and Nightfall

[lxl Ra lxl.5896]

Heyho,

 

I was wondering why in prophecies you could nearly skip all primary quests and missions and would still be able to get to the main outposts (Runs to droknar's forge ftw), but it kind of got limited in Factions and Nightfall? You had to do primary quests/missions to be able to enter missions. It kind of feels like you're given less freedom.