Introverts are not “shy.” I can address 300 people with a lecture - no problemo. I can testify before a legislative sub-committee, and advocate assertively but I rank very high as an introvert on Myers Briggs. I just renew myself by solitude in the woods. After dealing with others’ problems all day, I want no humans around me in the evening and weekends and am quite fine with my own company.
To introverts, people suck the energy out of you - natural settings and solitary reflection rebuild that energy.
This introvert gets charged from artificial settings and technology. Natural settings would still be preferable to people, though.
I’m off the scale extrovert in MBTI.
But MBTI’s definition of introvert/extrovert is not the only one. Some introverts are, in fact, shy. The MBTI, as you correctly state, is about preferences and how you recharge, but it is not the final word on what it is to be introverted.