People can and do engage with others more or less, so I don't think intro- or extroverted in that sense is fixed. But the understanding of introversion and extr

People can and do engage with others more or less, so I don't think intro- or extroverted in that sense is fixed. But the understanding of introversion and extroversion these days tends to be more whether you gain or lose energy in general from dealing with people. I doubt that feeling drained from (not) talking to people would change very quickly in someone. There are plenty of outgoing introverts.