That's a great point, but Morrowind also lets you pick from a host of different races and the class system to me is a huge part of the replayability of those games. You can play as an evil thief during one playthrough then as a chivalrous knight on the next. One of the biggest reasons why I hated Skyrim was because they allowed you to master every class on a single playthrough. What's the point of finding good loot if I can just craft the best weapons and armor? What's the point of playing through it again if I've experienced every class already?
Morrowind also had one of the best atmospheres in a video game I have ever experienced. The quests weren't tied to anything but the world was immersive (despite the graphics of the time). I remember going into a random dungeon in Morrowind and seeing/fighting a vampire for the first time and looting a single piece of ebony armor, a pauldron, and I felt a sense of discovery and adventure that I never felt in FO4.
I guess that's why they have different styles of entertainment. I've honestly never even finished Morrowind. Tried a few times. Couldn't get past the endless grinding. Bored out of my skull. Could not disagree more on 'immersive,' because there was nobody to interact with. You don't TALK to that vampire in Morrowind, he doesn't reveal any of his character or WHY you're trying to get that pauldron off him. It's just grinding.
Witcher 3 was what Morrowind wanted to be, but failed at miserably.
And I get replayability IF there's a reason to do so. If I couldn't get through the first playthrough because I was bored silly, why am I going to play again with a different alignment when alignments don't matter to how I interact with people anyway?
But I get that there's LOTS of people who enjoy the loot grinding aspect of games.
For me, the reason to do extra playthroughs in FO4, was to see how the choices I made effected the factions and the games finish.
Eventually once the mods have settled down for the console, I'll probably go back and try to do the ending where you can have the Brotherhood and the Railroad and the Minutemen ALL survive. I tried to do that on my second playthrough, but effed it up.