That's because this forum has the most loyal followers, who have been into TES for a very long time. On most other gaming forums, TES section is filled with kids, who started out with oblivion and refuse to play anything that doesn't have latest graphics. A lot of my friends are into TES, and none of them think oblivion is better than morrowind.
Ironically, we all play oblivion a lot more than morrowind though... Construction set allows for better mods in oblivion
There are plenty of loyal followers who don't post in the forum. Most people in this forum started with Morrowind, so a similar generalization to the one you made could be made about them. Truth is, the two games have a different approach, so one can't objectively be regarded better or worse than the other. One can prefer one or the other based on their tastes. I can assure you there are some time fans who prefer Oblivion (eg me), just as the forums assure me the opposite is also true.
As for the topic. If you can get past the graphics, they're definitely worth a try IMO. Daggerfall is worth playing just for the experience IMO. To see how high they were aiming. One may look at the faults and it has many (the weird dungeons that can take you hours to navigate, the randomly generated quests, the generated world, broken skills etc), but I've never seen a game that aimed so big. All the things they tried to put in there, all the customization option, the huge map that, even though generated, really make the world feel big, all the different kingdoms, the chances of becoming werewolf or vampire, the main quest that really allowed you (in fact, pretty much required you) to roam and build your character before you can tackle it and didn't shove itself in your face. Daggerfall was had plenty of mistakes in the implementation, but the scope it was aiming for was amazing..