Your comments makes me think that you have no family members inside that religion.
It it isn't just about lost years. Its about being shunned, it's about being hated for no other reason than you have a different belief than they do. Shunning hurts. The WT breaks up families. They take away a persons inheritance.
What are the most important things in life? If you are a balanced person, probably your first answer would be "family and friends". Now comes along a cult who threatens to take that away from you. Your children. Your parents. Your grandparents. Siblings. Your spouse. The most important people in your life.
It's also about screwing up your life and your children's lives, if you brought them up in that awful life-sucking religion. It's about a lot of things. Things which involve life's most precious assets' as Ray Franz so eloquently put it. Choice of spouse, whether or not to have children, the way you spend your time, what career choice or path you take, who you associate with, who you yourself shun because of your mind-controlled sorry state.... or if you saw or observed somebody in the congregation or your family die because they wouldn't accept blood.... Do you see? Are you beginning to understand?
The WTS is not a benign religion or a group of outwardly smiling happy people, there are fangs and teeth and brass knuckles under all that synthetic polyester....