Yes,and i can exactly tell you why.
Fast travel.
In Morrowind when you have to go to let's say, Gnisis from Balmora you say:''Curses,there are no Silt Stiders to that place,what the hell should i do now?Well,guess i'll just have to walk.Or fly if i have Levitation potions''.That will make you explore the background,clean some caves,tombs and such.
In Oblivion instead of walking you can always use fast travel.Instead if exploring the way to Anvil,you will just hit the fast travel,because you need to go there because of certain quest.
Next thing:Oblivion is a lot faster.
Do you know how slow a character is in Morrowind when he\she has 5 Athletics?Woah.........That's slow.
While in Oblivion,you won't notice such a thing.
Morrowind also had more how should i say.......a lot of stuff in a small area.While in Oblivion there is a lot of free space in the woods.....
Also Oblivion has a lot more ''boring'' loacations.Every cave is the same,every ruin is the same,the same loot everywhere,the same enemyes everywhere,and more importantly the same GOD-DAMN texture everywhere.Ugh,it's quantity over quality.....In Morrowind you could find an interesting Vampire lair,in Oblivion it's a cave like any other.......
Daedric Shrines and Dwemer Shrines are a lot more intresting too.Man i simply love Daedric shrines.
I could probably come for a few more reasons,but i will need some time.
