Every adoptee has a different experience. It's easy to think of adoption as a universal good because it gives children consistent and healthy homes, but that's not always the case. Adoption can be an exploitative industry. Mothers can be coerced into giving up their children against their will. Not all adoptive homes are safe, nurturing places for their adoptive children to grow up in. There are a lot of former adoptees who resent the system that took them away from their birth parents, and I would never begrudge them that grievance.
While some adoptees have bad experiences in their adoptive families, not all of them do. Some kids are taken away from dangerous situations, and getting adopted gives them an unequivocally good lease on life. That was the experience of 29-year-old Redditor, who was recently contacted by his biological siblings. He didn't react to meeting them the way they wanted him to, and the whole experience was a disaster.