Subquestion 1 (The Mismatch):

Has the "gift mismatch" phenomenon ever happened in your life—either as a disappointed giver or a less-than-thrilled receiver? How did you feel in that moment, and how did you handle it?

I cannot remember the feeling. Coz I forget the last time when I received the gift...

Subquestion 2 (Defining the Terms):

How would you personally define a "gift" and the act of "gifting"? In your view, what is the fundamental difference between giving a gift and simply sharing something with someone?

The fundamental difference is that giving a gift is an act that one needs to specifically do that. And sharing is a "by-the-way" thing.