Knowing how to braid is certainly not essential to having long hair, but it certainly can help make your hairstyle repertoire more interesting.
Whether you choose a braided hairstyle or whether you use an accent braid or two to a regular bun, you can add more panache to any hairstyle.
Most people can do a simple three strand braid. With a little practise, it's not difficult to learn how to French braid. That simple knowledge can really spice up the way you wear your hair and can help to prevent feeling the boredom that some people experience when wearing updos day after day.
Once you've mastered a French braid, then it is very little trouble to learn how to make an inverted French Braid, which most people refer to as a Dutch braid. The only difference is that as you make your three strand braid, instead of crossing the outer strands over the middle strand, you cross the outer strands UNDER the middle strand.
The difference in appearance between the Dutch Braid and the French Braid is striking, and both are just as easy to make, but you've now doubled the various braided looks that you can choose from.
Later, when you're more comfortable, you can learn more complicated braids, but once you've learned the basic three strand braid, you can really vary your look.
French braiding can also be handy to anyone growing out bangs. I found that an invaluable tool when I was growing out my own bangs. I was able to French braid just the top of my head, and it didn't even appear that I was in the bangs grow-out phase.
Braids can add elegance to a style, or on the contrary, a casual bohemian look, depending on how you put it together.
Your hair doesn't even have to be that long to begin learning to French and Dutch braid. If your hair is long enough to pony tail, it's long enough French braid. I suggest that if you don't yet know how, then learn. It's a very handy thing to know.