Legally speaking, cash is, and will remain, valid tender for settling debts, and creditors in general may not refuse it for an outstanding debt.

However a seller is generally allowed to refrain from selling (bar certain specific protections), and thus the seller is allowed to not create the debt in the first place. This is why, while cash remains legal tender, one could legally end up in situation where it's virtually impossible to buy certain goods or services for cash.

Nb., I support the general idea of this legislation, specifically for reasons of privacy and practicality.