or lab grown leather? (but it seems leather is not a very interesting target for substitution as there's no market for it? https://www.latimes.com/business/sto

or lab grown leather? (but it seems leather is not a very interesting target for substitution as there's no market for it? https://www.latimes.com/business/story/2019-08-18/america-is-obsessed-with-beef-but-it-has-no-use-for-hides-so-leather-prices-plunge https://www.latimes.com/business/story/2019-08-18/america-is... though this is from 2019)