I don’t think they/are were Jews, per say. Kenites saying they are Jews might be more appropriate. You know, the ones that instigated the murder of Christ. Yeah, they riled up a bunch of folks against him, but that is no different than they do today.
There are groups of very orthodox Jews who will not exchange money, or engage in commerce of any kind, or use a car, or a phone. There is an apartment complex in MD where many of this particular branch of Judaism live(d), that has its own shul, who are *that* observant. They sure are Jews by anyone’s standard.