Can a person who doesn't like to talk much still become a good lecturer? Can a person who doesn't like to talk much still become a good lecturer/academician? Do you have any experience like this or know anyone like this?
Absolutely, a person who's not naturally inclined to be a speaker can become a good lecturer and scientist.  One of my best professors, actually, was a person with such inclinations.  Finding that speaking was not something that he was good at, he turned it into an object of study and began collecting heuristics about what made a good and effective talk.  By studiously applying these heuristics to his own teaching and professional communication, he could at least ensure that his talks did not fail on any identifiable dimension.  

Talks need to do a lot of different things at once: holding attention, identifying key salients, speaking at different levels to different parts of the audience, providing "breadcrumbs", etc. Because of this, it often turns out that it's much less important to do any aspect brilliantly than to make sure that no aspect has been neglected. This professor might not have been a brilliant and exciting comedian, like some who are natural lecturers, but he often gave better lecturers than the naturals.  The more natural lecturers were often simply less consistent: following their enjoyment and intuition produced brilliance in some aspects and weaknesses in others, while his stolid application of heuristics ensured an across-the-board solidity of presentation.

In short: ultimately, it's not a matter of talent but of choices for how to invest in acquiring skills.