Bad? According to who?
I can tell you right now that more people have heard of Charlie Sheen than President Obama, the Soviet Union, Tamriel, or even Bethesda.. If it's sales you're after, adding pop culture to videos games is never a bad idea. TES games would attact more players, none of the old players would stop playing (keep saying it isn't an addiction; I don't believe you), and we'd all be "winning".
Then again, nevermind.
Too late for that, a question deserves an answer, no matter what the question is.
It′s bad because popular does not equal to good, sure the established player-base would keep on playing, but the overall enjoyment would be reduced, a lot of players pick up on a game because of good reviews, the game would only get worse reviews from the established player-base that enjoys the feel and atmosphere of the game, bombard it with specific (with this word I′m talking about things you can′t mistake as an attribute that was not derived from something very specific in real life, having rakes does not make one go "Oh no, a rake! Just like in real life! Now rakes in real life just popped into my mind!" but have something like let′s just say Charlie Sheen, and it′s pretty hard not to bring up a mental image of the real person, that is, it is too specific not to break your attention away from the game a tiny bit) real life references and the game loses its charm, after all TES is not popular because it has good game mechanics, it′s popular because of how it can svck you in, how immersive (gggrrr red underline, put the word "immersive" into the English language already!) it is and how good the story is.
Ruin the games selling point and you ruin the respect people hold for the series. And things like these can easily escalate to huge levels. I have nothing against references to former games or individuals within the game world, like they could have painting for sale by the guy with the magic brush in Skyrim, but please don′t have too many references to the real world.