From the existence of the phrase "based and redpilled", we can see they're different things- or why mention them?
To be based is to have a certain effortless confident, self-assured fearless character and disposition towards the world. Someone who's based doesn't care if what they say is controversial, because they're too cool to care, but they won't say controversial things for the sake of it- attention-seeking is cringe, it's the act of a weakling who has to scramble for whatever power he can filch off others. The Based one simply says what he believes to be true when he wills, irrespective of social norms. He could pretend, but has no need for pretense, because he does not fear reprisal.
Being red-pilled is something else; it's a certain kind of enlightenment, a disturbing revelation about the nature of the world. When you take the red pill, you're throwing aside comforting lies and confronting the hidden/evil truth.
What exactly that enlightenment is varies from subculture to subculture- the imagery of the red pill has been used by lots of people, and there's a whole range of pills now; the bluepilled are normal people who still accept the lie, blackpilled people are redpillers who have fallen into despair and hopelessness (where it's implied that the red pill usually implies a call to action, the black pill implies apathy- 'just let it all burn', and blackpillers view redpillers as naive in their desire towards action, which will be pointless at best and counterproductive at worst), the white pill which is a hopeful rejoinder to the black pill, the iron pill which says you should work out more...
A lot of these pills act as revelations to previous revelations that recontextualize the previous pill's lessons and worldview, and in the face of all this uncertainty and flux, you can imagine there's a lot of anxiety.
This is where 'based and redpilled' comes in. The based attitude quenches the neurotic anxiety of the pill-seeker's revelation, while the information in the revelation itself- paired with the confidence, self-assurence, and courage to act on it- lets the Based and Redpilled avoid the pitfalls others fall into, and stride forth as more than their peers, as the union of chad and virgin, as the guy who says the n-word on twitter and doesn't get fired because he's his own boss.
