In my super humble opinion, technical interviews mainly test communication skills and, only then kind of, technical abilities.
By 'communication skills' I categorically do NOT mean being able to strike up conversations with everything (people, furniture). I'm going for 'analytical thinking' and structured communication vs yapping away.
In fact, this has nothing to do with personality (extrovert vs introvert). If anything, the more you speak, the higher the chance to royally embarrass yourself (been there, done that, millions of times, last week).
A few tech interviews' non-tech recommendations from my side:
1. Analyse the question:
It's a common technique that interviewers intentionally ask vague questions. Why not? People deal with painfully imperfect information all the time.
My rule: Clarify, then clarify again, and again - nobody ever penalises for that. Or, you can blindly swing and probably miss...
2. The 2-second rule:
You have understood the question and you know the answer. Your brain delivers 15 pearls of wisdom for you to cannonade the interviewer with.
2 of those are spot on. The rest, well...
Think of a structure to your answer (2 secs). Maybe, prior to answering, even share this structure with the interviewer.
Self-confidence boost at its finest :)