I think TOO many people 'discovered' The Elder Scrolls with Morrowind, so that's sealed the deal as being their favorite game. It was their 'first'.
Post-Morrowind, It's difficult for many to go back engine-wise (lol OMG they used SPRITES!!!) To appreciate Daggerfall or Arena for what they were.
And take off the rose colored glasses people. Yes, Daggerfall was a bug-fest. Yes, I learned the "Daggerfall 'shuffle'"(saving OFTEN & cycling through save slots to ensure a somewhat recent stable save
) AND the Daggerfall 'shuffle' served me well in Morrowind, the CTD game of the year
Not to say I didn't love Morrowind... I did! I'm just attempting to show WHY some people have unintentional bias towards one game or the other & it's a hurdle to go BACK such a large step (Tech-wise) and not have that affect your opinion.
*Queue Rabish promoting nethack
*
Yep, that is right. Maybe I should have splitted the poll as Absinth82 did, first asking people who have played all games, then those who only could compare MW and Oblivion. Or maybe, to be closer to what you said, ask the opinion of people who discovered the serie in the natural chronological order, and then those who did it in a more exotic one, like playing Arena after MW, before testing Oblivion before they finally download DF...
Technological evolution is a very hard bias to remove to compare the serie evolution. Ignorance of some of the games is even a bigger bias! After all, Arena and DF devs are "retired" since a long time, so should be most of their players (which are already fewer than MW and Ob ones).
At least, Oblivion having a bigger commercial success than MW, it is interesting to note a clear trend toward people considering something has been lost since TES III, even if Oblivion is technically better than MW.