I wonder how many of those children are introverts and how stressed and exhausted they must be. I worry about their self-esteem and their ability to function. None of us can act socially when we are run-down, stressed, and frustrated. Let's learn to let introverts be themselves without emphasizing so much the time they spend with others. Life is about learning who we are and what our purpose might be here on this earth.
All life exemplifies balance, including introverts and extroverts.
Let's accept that balance and revel in it rather than reject it. There is a place for everyone where they can fit in, energize themselves, and feel comfortable.