it's still the law of the land. an individual U.S. citizen that earns income abroad still owes U.S. federal income taxes. corporations are granted legal personhood and so are responsible for their taxes in the same way an individual person is.
It's the same for Apple, it's just more convenient for them to structure their overseas activity as an overseas corporation, than it is for most natural persons. (And they got a sweet tax deal from Ireland)
the reality right now is that that is the law and corporations based in the U.S. go to great lengths to avoid their legal tax burdens.