On the other hand, adoptive parents don't insist that there is literally no difference between them and a bio parent. In fact, if you take adoption home studies and do the training (in california at least) to adopt a child, you will learn the many ways in which you are not like biological family. My wife and I went through most of the process, but never ended up going through with the adoption (open to it in the future). We were told in no uncertain terms that pretending you are basically a family like everyone else and not being truthful with your child about their origins is bad for the child.

Thus, it should not be offensive to say things like 'trans women are biologically male, thus have biological male advantages in things like sports'. This is a controversial statement. However, there is a section of the trans community who will insist that trans women are actually literally women like all other women.