As far as ethical materials go you can’t really get better than wool.
The sheep need the hair cut.
Nothing dies for it.
Sheep live pretty much wild for most the year.
Placed correctly they maintain a landscape and help the wildlife that live there to thrive.
Doesn’t use Vast Quantities of land for little product.
Not draining inland fresh water oceans.
Been spending thousands of years perfecting the genetics for this purpose.
Comes in many different kinds of uses.
And the animal it comes off is fully edible.
My main issue with it is it has fallen so out of fashion that it pays the farmers who make it more to transport it than they get per fleece, and people have really fucking weird hang ups about the ethics of giving a sheep a hair cut.
Sheep can get infested with wool maggots if they are not shorn.
Also an unshorn sheep can drown if it falls into water, just by the sheer weight of the water its wool can absorb, dragging it down.
A Tunis sheep can live in a large doghouse, and staked in a different place every day, will mow your lawn (buy they get lonely. Buy two).
Light shearing nicks heal fast because the sheep’s waxy lanolin coats their skin. Though most sheep farmers won’t Nick the sheep bc it gets blood on the wool.
Sheep farmers MUST treat their sheep with care, because any little thing that upsets sheep affects the quality of their wool.
Even “natural” fibers like bamboo take TONS of water to process and alkaline dyes to color them. You can dye wool with unsweetened koolaid.