I think a lot of people are not aware of how it is almost impossible to find an adopted relation.
If this adoption went through official channels the adoptees new name is only available to trained intermediaries, adoptions were usually a long way from the area the birth parents were from.
My husband had never seen his original birth certificate only his adoption certificate so he had no idea of his parents surnames or where they were from.
So just because someone has not made contact, it is not always because they didn’t want to know.
Another consideration is the circumstances of conception, imagine finding out you were the result of rape or incest, it does happen sadly.
Finding adopted relatives is always best left to the professionals and must be clearly thought out first.