I really think you're not remembering Morrowind in a clear light. You're remembering the extremely rare exceptions as the rule. 99.9999% of the Dungeons in Morrowind were tiny, single-path deals, with little to recommend them.
That's precisely what I'm saying. Morrowind dungeons are small and straightforward, or long and complex. Skyrim has long, but straightforward dungeons which makes them tedious. Even in the case of small Morrowind dungeons, you still had side rooms and short hallways that led to places other than the dungeon "end". I can recall one or two dead-ends in a Skyrim dungeon, the vast majority simply lead you through a long hallway with the occasional open room
(Random selection of Morrowind dungeons)
http://images.uesp.net/c/c8/MW-map-Salmantu.jpg
http://images.uesp.net/a/ab/MW-map-Rissun.jpg
http://images.uesp.net/8/87/MW_Map_Assemanu.jpg
http://images.uesp.net/4/4e/MW-Maps-Berandas.jpg
http://images.uesp.net/a/a2/MW_Map_Dun-Ahhe.jpg
http://images.uesp.net/2/2e/MW-Map-Endusal.jpg
http://images.uesp.net/9/9d/MW_Map_GinithAncestralTomb.jpg
http://images.uesp.net/f/fe/MW-map-Ilunibi_Caverns.jpg
http://images.uesp.net/9/95/MW-map-Pinsun.jpg
http://images.uesp.net/1/18/MW-Maps-Saturan.jpg
http://images.uesp.net/6/6c/MW-map-Tin-Ahhe.jpg
http://images.uesp.net/1/13/MW_Map_Valenvaryon.jpg
http://images.uesp.net/8/83/MW-Maps-Yakin.jpg
These are the kinds of dungeons I like. They aren't long for it's own sake. They're designed like a real location would be. They aren't leading you by the nose to some ultimate, final boss room with big, leveled chest. 99 percent of them
will have hand placed loot. There will be unique items hidden behind a boulder in a tunnel cave in. There will be magically trapped diamonds. None of this is present in Skyrim, you simply move forward. And moving forward inevitably leads you back to the beginning so you never even have to backtrack. It's predictable, and because it's predictable, it's boring.