Never said Oblivion is a bad game. It's just a bad game compared to Morrowind.
If any other developer, like maybe Bioware had made it, it wouldn't be that bad. But Bethesda is capable of so much better.
I strongly disagree. People always say "it's a bad game compared to Morrowind" as if it were a fact. Unsurprisingly, I don't like or agree with that. It's just as valid as saying:
It's not that I don't like Morrowind, but it's a bad game compared to Oblivion.
It doesn't matter how it was made. People would complain, and BioWare is especially incapable of making an Elder Scrolls game.
In defense of Oblivion, I will only list facts in this post. According to a video game world record book, Oblivion is:
the best-selling Western RPG of all time and the second most critically acclaimed Western RPG of all time(second to Baldur's Gate II)
According to that same book, Daggerfall has the largest gameworld in a Western RPG. Actually, perhaps the claim that Oblivion is better may be more valid(don't worry, I'm kidding), but as far as Bethesda is concerned, Oblivion is their best work and it's what put them at the top. Perhaps success is what makes people say "it's for casual fans", but success is success.