Oh my various gods. I am actually reading - and loving - a massive philosophical debate regarding My Little Pony Friendship Is Magic. But, I must highlight this fascinating comment. Also, I have learned that this season finale is just Part One of a trilogy, which might mean that the status quo will return or things will just get interesting from now on. Also, this comment is kind of awesome and I wanted to discuss it - oh my gods, is this turning me into more of a Brony, or does it just mean I like philosophy in everything? Probably the latter.
Also, screw spoilers. I was late to the party, and anyway the secret has been out for a while.
Ack, you're getting too philosophical! Again, while I'm not necessarily saying you're wrong, you have to remember what the canon is -- a (sometimes overly) straight-forward and light-hearted cartoon that little kids watch; yes, a cleverly written show with an adult audience both admiring and often with insatiable standards...but again, little kids watch this: they aren't going to get into complex areas of logic and reason.
Their are no "maybes" or "most likely" with this - the cutie-mark represents, not just your special talent and what you are naturally gifted in, but essentially your future - and not just your future, get over it, but your happiness...your 'true self', what makes you special, the road and life that will make you happy; it's why their is so much simplicity and eagerness for foals to find their cutie-marks because they don't have to necessarily think about themselves and their future in the broad way humans do...it's just a matter of figuring out what they are good at (hence, the CMC trying all sorts of ridiculous things to make things interesting and funny) i.e. what their special talent is, which doubles in what makes them happy and fulfills which also parallels in being their destiny and what they are meant for in life i.e. what will make them happy like no other.
The whole thing is unbelievably simple and straightforward, and that's the point of the canon; it's how it works...everything we are thinking of are genuine wonderful questions because they are normally complex abstract philosophical discussions, but as before, this is a children's cartoon....they are not going to go off the wall:
1) Foals don't have to think too hard about their future - not like humans do...it's just a matter of figuring out what they are particularly good at, narrowing down what their 'special talent' is which...
2) Will appear on their flank as a "cutie-mark" when they realize this; which doubles as the realization of their life's calling and what they are "meant" to do which will bring them a happiness and fulfillment like no other...something called "destiny".
3) They wouldn't get a cutie-mark for anything other then something they were 'meant' to do - meant to in the sense of being something they were genuinely good at ('special talent') and exceptional, and fits with their personality, and also in the sense of being an indication of what they are meant to do in life that will bring them a happiness and fulfillment like no other...a state of being that is truer and more representative of themselves like nothing else -- hence, their "true selves".
4) Hence the extreme importance of finding out what their cutie-marks are for, and why things are so awkward and difficult for foals and why "Blank Flank" is such a stigma...ponies can't make a life for themselves that is happy and fulfilling doing anything else -- someone with a bread-making cutie-mark can't start making fruit and expect to be happy, or live a life that's as happy (or happy at all)...they will inevitably and continuously be miserable forever and ever because they are not doing what they are meant to do i.e. what they are naturally and exceptionally good at i.e. what fits best with their personality and character i.e....they are ignoring their 'true selves'.
This, my friends, is why none of the Mane 5 questioned anything when the cutie-marks were reversed...you have to understand just how dependent they are on cutie-marks - everything is unbelievably simplified in their world, and also has it's drawbacks....because even though they realized they were not good at what they are doing, they refused to even try to think about doing anything else, and nobody else tried to help them, simply because this was their cutie-mark -- of course Rainbow Dash must take care of animals, because it's her destiny, it's what she is meant to do and must be what she's good at, it must fit with her personality, her special talent and what makes her happy like nothing else will....because she wouldn't get a cutie-mark for anything else if none of that were the case.
Ergo, despite being unhappy, despite being unsuccessful....nobody helped the Mane 5 and nobody else bothered to help them in this time-warp episode because, well, "it's got to be my destiny....and it's what my cutie-mark is telling me!"
This is also why Twilight, who by the way, behaved quite appropriately actually for the situation and even asked about books, didn't ask too many questions nor did anyone else...because again, the comfort of knowing this is what she was meant to do all along, what she is good at, what her cutie-mark must have always meant...this is a time for celebration, not a time for asking longevity questions!
Destiny is always a comforting simple and explicitly good thing in their world, no.questions.asked.
Also, as I have just learned: Lauren Faust, the creator herself, said that while Twilight Sparkle becoming an alicorn was not what she had planned, she no longer works on the show and won't undermine what the writers and showrunners are currently doing. Also, Tara Strong joked "Everypony relax, Twilight is not leaving her friends, however the voice acting will be taken over by Morgan Freeman."
The point is, the status quo won't actually change; it will just mean that a princess alicorn will be living in Ponyville library while still hanging out with her friends. Hell, if I became some respected celebrity, I wouldn't leave my friends either; although I might buy a bigger house.