Generally, I agree. If people want to investigate the meaning of racial identification and whether it's possible to change one's race, they can go and figure that out, but it really has nothing obviously to do with transgender identity and experience. The comparison between "transracial" and "transgender" only seems to be used to undermine transgender people, or in an intentionally disruptive "just asking questions!" way that amuses the (white cis) asker and annoys most other people. If someone is seriously interested in the idea of whether race is mutable, they can go and do a serious study of that. But when they casually tack on "...kind of like changing genders!", it makes their inquiry seem less serious and makes it appear as though they have another agenda.