> That in practice it does not work as intended means it is bad law and needs tweaked.

In what specific, concrete ways does it not work out the way you think it is intended?

> One way would be to say that all behavior "off the clock" and all attributes of a person not related to the job are protected. Another way would be to say nothing is protected.

Those are obviously potential rules, but I don't see that either of them is closer to any reasonable interpretation of the intended result that antidiscrimination laws are intended to serve.