What can we do though? I know we're all livid about this decision, but most of us are too shy to publicly outcry about this.
The only productive thing I've seen is to sign these petitions:
Tell MasterCard, Visa & Activist Groups: Stop Controlling What We Can Watch, Read, or Play https://chng.it/b2pMbsLvdg
Mastercard: Sex work is work. End your unjust policy https://action.aclu.org/petition/mastercard-sex-work-work-end-your-unjust-policy