I'm not sure what the question is. Do you mean, "Why is being surreal a problem?" or do you mean, "Why do I think that there are problems other than it being surreal?"
To the former, it's because among my several aesthetic desires for play is the sense of exploring something real. One of my favorite authors is JRR Tolkien, and he achieves in his work a certain quality of being a subcreation, of being alive, of being real, and of being tangible that I associate with the best sorts of fiction - this quality of transcending their immaterial state and though imaginary and fictional and insubstantial, nevertheless having qualities like things that are real. It's what I associate creativity with - reification of the things that are not.
To the later, it's because there are I think problems beyond the breaking of the fourth wall and the interruption of the immersive qualities of play. For example, I think you risk being both the person who introduces the problem and the solution, which isn't the experience of play but rather is the experience of authorship. And I think the experience of being a partial author is in terms of play, more satisfying than being an author. The joys of authorship are different, and involve the satisfaction of having made something, but the process itself isn't in necessarily (and is rarely) fun. It's work. You do it anyway for what you'll make in the end, and for what you hope to communicate. But I don't think of it is as playful.
You could just as easily say that before the FATE point was spent there may or may not have been a chandalier because that detail didn't matter and the expenditure of the point merely solidified that detail as something that did exist by making it matter. In other words, the player has the agency to bring something into focus that was previously out of focus and, consequently, formless.
Yes, but you can do this without a metagame mechanic, and without giving the player explicit authorial authority. A player can draw attention to the fact that this room, because of the nature of the room that has been described - "a ballroom" or "a grand foyer" - probably has a chandelier, where before no one was paying attention to that likely fact. And a player can do that in any setting and with any system we choose. Bringing something into focus is something a player can do if they have any amount of agency in play at all. But if a player can literally invoke the chandelier into play as an unquestioned solid fact because he wants or needs one, it's a very different thing.
So your argument is that GMs of indy games can't be trusted to entertain because they run indy games?
Wait? What?!?!? I didn't say anything like that at all. My argument is that advocates of Indy games appear to act as if the authority of the GM needs to be mitigated because the GM can't trusted, and yet the games that they produce tend to contradictorily require very high levels of GMing skill. Presumably if you have a high skill GM, then Indy games can be quite fun (and in fairness, there a lot of features of a game like FATE I really like). But then again, if you have a high skill GM, you don't need to worry about what the system is like.