I know you said no wool but not all wool comes from industrial farms. I am big into knitting and a big lover of wool. All of the wool I work with comes from small scale farms that live their sheep more than themselves. I really recommend looking for local, small scale farmers who shear their sheep and create wool products. If you dove into the knitting community you would find a community of people dedicated to sustainable fashion who live their sheep. If you really want to go further look into knitters/producers who are part of “shave em to save em”. It’s a program built to preserve traditional sheep breeds that are threatened or endangered. The whole premise being “make their wool valuable so they are preserved by farmers”. You are right about commercial wool being tricky but there are tons of small scale producers that will make quality 100% wool socks from sheep that are well-loved.

ETA: I almost never post on reddit so if I formatted things wrong I apologize, but that lends credence to how much love I have for wool and small scale shepherds!