I agree with a lot of what he is saying the only thing is life doesn’t always permit for you to take it slowly.
I consider shy or introverted by this definition Definition of Introvert -- What is an Introvert? more of a personality trait as oppose to it being a mental illness, but irrational fears controlling a person definitely needs to be addressed and most likely in the manner he was talking about.
There’s a few in that thread that think they communicate poorly, but they did quite well in that and many other threads I have seen.