I see your point. I actually semi agree, that people should have the right to fire for nearly anything. However, what if your customers didn’t like blacks or Jews? You can’t just avoid black or Jewish applicants.
If someone doesn’t like blacks or Jews working for me, they can go elsewhere. Good riddance to them. Race, gender, age, religion, etc. have no place in this. Well, mostly. If someone is Islamic, fine. If they promote the hate and evil of it, no. Same with participating in BLM or JDL, that goes beyond being member of a group. Actions, which are a choice, have consequences.