The Age Issue

Before I yammer on, there's a really excellent post here by Dapper Kid on fashion, gender roles, stylish men, and confidence (to name a few highlights).
With the poll going on, on the right, I'm certain many of you saw this post coming. With the votes tallied a good majority of you believe that age is just a number and I concur.
To start, there is the whole phrase "you are as old as you feel." There is much merit to be found in this statement. While I am still young in years, I have never felt immature or goofy or even like a party-er, so is it really any surprise that I don't usually wear super high hemlines or tight fitting clothes and I definitely don't buy into trends? While picking up some acid wash jeans or trading my secondhand flats for some flips flops may youthen my wardrobe and make me look more similar to the nearly uniformed masses (heck, I could even make an attempt at hipsterdom), it doesn't change the fact that I work in an office, enjoy making puzzles, and listen to National Public Radio. I'm more likely to complain about mysterious pains in my back than how I got so wasted at that party last week--so yes, I might not dress like most twenty-one years old people know, but I'm not a twenty-one year old you know or are likely to meet in a hip hang-out. My own grandmother can be quoted as saying about me, "she enjoys the quiet life, doesn't she?"
Further, where does this concept of dressing one's age come from? And who makes these rules of propriety? Supposedly, if I dress too young or too old, there is a "proper" way to be dressed. Which honestly, let's just say it now--that's stupid. If I listened to every rule of proper dressing I wouldn't wear white after Labor Day (or is it before..?), wear green and yellow without a color in between, mix gold and silver jewelry, etc, etc. Also, let's consider the antiquated notion of what one does at one's age anyway. When these rules were followed religiously by my age I probably would have been wed with children by now. What women do and when they do it, is changing. Through modern knowledge I can have children much later in life than previously believed possible, through proper diet, exercise, and a bit of medical help I can also live longer, and with all my options before me I can forgo marriage and children entirely and follow whatever pursuits I desire. So yes, women don't dress as "age appropriately" as they used to, but they also don't live the same. Maybe our wardrobes are merely evolving to reflect our lifestyles.
Back to the second question: who makes these rules? I'm always intrigued when people (anonymous commenters, or those worst dressed list writers) tell others what to wear, because WHO are they? How do they dress that is so fabulous that makes me care what they think about my style? I'm very reluctant to give fashion advice even when expressly asked because I'm not a fashion expert and to say "here is what to do" is another way of saying "I'm right," which implies someone else to be wrong. I try not to judge other people's decisions stylistically because I allow for the error of perspective (it's just my opinion and who am I to say it doesn't work if they like it?), so it would be nice if others could be a little less egomaniacal and allow for the same flaw of perspective in themselves. Because if I don't listen to my friends, why should I listen to people I don't even know when they advise me on what to wear?
Finally, if you ask me directly if I dress my age, the answer is no. Because I don't dress according to age at all. I dress according to situation (read office job at Conservative school) and mood. It's pretty ridiculous to say I dress older than my age since I have never once been mistaken as older than my age, even in the most "age appropriate" looks conceivable (even in a work environment and professional wear people still think I'm a young teen...). It's also amusing to think I dress too young when I know when I was younger I lacked many of the sartorial knowledge and confidence I now possess. Let me finish with this: when I wake up in the morning and face the myriad of options facing me from my closet the last thing on my mind is "what would a typical twenty-one year old wear?"
Outfit details: dress- some shop in Japan, jeans- Hot Topic, shoes- Urban Outfitters, belt- secondhand