I think there are a variety of potential solutions, but one where the public marketplace is taxed/polluted by a private entity in a way that can't be avoided isn't an acceptable status quo.
Requiring FB to provide a paid ad-free option with a price commensurate with their cost of providing service would be one approach. Prohibiting them from actively breaking adblockers would be another. I wouldn't wholesale ban ads, but banning them on FB marketplace would be reasonable - either we get an ad-free marketplace, or FB abandons the product and we get alternatives.
Requiring FB to provide a paid ad-free option with a price commensurate with their cost of providing service would be one approach. Prohibiting them from actively breaking adblockers would be another. I wouldn't wholesale ban ads, but banning them on FB marketplace would be reasonable - either we get an ad-free marketplace, or FB abandons the product and we get alternatives.