Actually, yes.
Adoption is trauma. It may be the best outcome in a situation that is less than ideal, but is a traumatic event for the baby. It might have a good "ending" for the child if they form a successful healthy attachment with the adoptive parents.
However, good adoptive parents do not cancel out the first loss, the first grief for that baby that is losing their birth mother. It is always a traumatic event.
Not every adopted person will be traumatised, but a high percentage of will. It can hit later in life, perhaps after having children of their own, or after adoptive parents die, or after finally meeting birth family. Adoptees as a group have unusually high rates of addiction, often trying to self medicate. Trauma can lie buried for a long time.
Many, many adoptees are speaking out now about the trauma of adoption. It is the only form of grief (losing the birth parents) where the person is expected by society to be "grateful" (for the new adoptive parents, taking them on) and have their grief totally invalidated in the process.