Interesting. Guess it’s good if it will help reduce “forever chemicals” in the long run.
I’ve never found a rain jacket that holds up to extended downpours other than the “rubbery” type materials. Spend a fair amount of time doing yard work etc with cheap no-name rubbery pant and jacket in extended rain without being soaked through.
Not sure what the chemical composition of these entail though.
The article mentions using waxes as an alternative and historically think people wax/oil leather to be water-repellant. It probably works well but is heavy etc