Unironically, vegans need to be advocating for more and better sheep, llama, and alpaca farms. Wool is one of the best fabrics we have in terms of versatility, longevity and most importantly, insulation. Even wet, it retains 80% of it's insulation potential.
AND IT DOESN'T SHED MICROPLASTICS
Like, there's literally nothing you can do to a sheep that's as morally reprehensible as dumping plastic down the gullet of literally every other living thing. You wanna talk about animal welfare? Talk about reducing the amount of microplastics produced by nylon, polyester, and spandex.