Personally it seems a little silly to try to make fiber from the top of a pineapple, but what do farmers/gardeners do with the plant itself?
The whole plant has leaves large enough to have genuine use for fiber. It seems similar to the plant from New Zealand that many people grow as an ornamental in North America. I recall it's perennial.
My sister grew a pineapple top indoors one winter - it's leaves were plenty long enough.
Getting fiber as a bi-product from food production or from perennial plants makes much more sense to me than abusing soil to grow all our clothing as a mono-culture or to use artificial materials which are toxic to produce and don't biodegrade into soil.