That last bit is a false equivalence - we have no way with current science to truly introspect the "thought process" of another human, so functional judgment is the only kind we can exercise.

With AI - we built it. We can read the code that's running. We can make a distinction, in cases where output or behavior is identical, whether it's a neural network or a 12-million-line switch statement - and that value judgment means something to our determination of intelligence. There are plenty of ways other than (or in addition to) output to determine the "intelligence" of a machine that we simply can't exercise with other people.