I don't know. I've not thought about marriage in game. But, if I were Bethesda I'd probably sell sixy undies DLC just to take advantage of the desire some have for it... lol. Just imagine how much they could make from "talk dirty to me" dialogue add ons. I guess it's all just symptomatic of the change in what people want from a game like Skyrim in modern times. Loot, Laceration, and levels just no longer cut it. Err.. was that an unpardoned pun?
Uuugh - why do you think people interested in being able to interact more with NPCs boils down to wanting digital undies and virtual dirty talk? Never mind mods have done that before and 9 times out of ten they are as awfully juvenile as you'd expect.
Have you played some of the other classic RPGs, pseudo-RPGs etc that allow you to have a party, follower, crew etc and make an effort to let you talk to them and have them have something to say back?
In BGII you had heaps of possible companions, only four of which were romance options (and like real life some of those could be viewed as bad ideas/work at it kind of romances). And for romance options there was no sixy undies or dirty talk (Vircona aside)
And symptomatic? You do know RPGs have been around for decades don't you? And while plenty of DnD sessions boiled down to murderhobos hacking and slashing there way to god-hood there were lots with.... wait for it, you might want to sit down, this could come as a shock.... RP.
Yes, it is symptomatic of the change people want of RPGs in modern times - that they can do more than just kill stuff* :facepalm:
* If not there are some total conversions to Doom games that turn them into hack and slash as opposed to run and gun. Lord knows RPGs need to go in that direction, right?