Behaviorists were operating under the misconception that something can't be both subjective and objective at the same time. It took Cognitive Psychology to rescue us from this sorry state of affairs. But for years, those who wanted to do Cognitive Psychology academically were blocked from publishing and getting tenure, etc., by the entrenched Behaviorist establishment.
These days we know that via using FMRI, for instance, psychologists and neuroscientists can often determine objectively more about some of your own thoughts than you yourself might know. Or they can sometimes know what you will come to decide before you believe yourself to have decided. Etc.
But certain mental states (i.e., phenomenal ones) seem to have an inherently subjective component that cannot be studied objectively at all. Or at least that's what someone who believes in the "hard problem of consciousness" will say. Others will say, "Pshaw!"
(P.S.: Assuming that a "God's view" of the problem has to exist?)
I'm suspecting that physics might end up in a similar situation than mathematics, where we find out that we can't objectively prove everything - and either we'll have an epistemological breakthrough allowing us to deal with subjectivity in a framework that has still some resemblance to a scientific method, or... we won't.
(Personally, I'm hopeful that the Hard Problem can be "dissolved" - and this "philosophical zombie" concept just seems to me to be misguided, just like the concept of aether was.)