The world in Morrowind was vastly superior and way more varied than Oblivion. Morrowind was also the last time where you could actually kill all the important NPCs, including the main quest givers, while Oblivion took steps to protect the important NPCs. Thus making Oblivion the beginning of making the franchise way too casual, or AAA. Regardless, the liberty to off anyone was liberating. Oh, and the Oblivion Gates suuucked.
While I can give you the fact that the whole RNG/Dice Roll combat from Morrowind is terrible, cuz it was, and it is, when it comes to everything else, Morrowind is simply superior. Sure, not perfect, but it was a step in the right direction before Bethesda decided to fall off.
Morrowind is certainly the one game I wouldn’t mind Bethesda revisiting. Especially if they get rid of that god awful combat system, bring back the liberty to take out important NPCs (Obsidian still does this), and better sign post quest markers without relying on arbitrary HUD elements or AAA arrows.
Oblivion is when Bethesda took an arrow to the knee and started their decent into Midness.