Birthday presents is a formalized way to practice the good social etiquette we're supposed to be learning. Yes, it can be painful to be grateful receiving but it teaches us grace. It also teaches us to be more mindful when we ourselves give a gift. It can be painful when we give someone something they have no clue what to do with or feel inadequate giving something that's "all we can afford". But not doing so robs us of the opportunity to get it right. Sometimes a thoughtful cheap gift, or a gift handmade made with more friendship than skill is received better than an expensive well crafted gift. Not giving gifts or opening them at the party may save a child from disappointment, but it also robs people of the opportunity for joy.
Everyone should make their own traditions for gift giving, parties and celebrations, but the article wasn't about that. It was about making birthday parties dull and joyless because the author is feeling sorry for their self.