Don't we allow pretty much everybody to discriminate based on viewpoint? Except the government, and common carriers. Nobody is going to force me to do business with Nazis, for instance, regardless of any executive order.

Unless the employee is in a union, unless you're a landlord in a state that protects political ideology in housing, unless you're an employer in a state that protects political ideology, unless you're a hospital that takes Medicare.

Lots of government rules that force you to do business with nazis