I think the issue comes down to the fact that only a relatively small percentage of people consider a recently-created embryo to be a child or a person.
That's sort of the reality here- even without Roe v. Wade, I doubt you would be able to find more than a handful of States where the majority of people would ban IVF treatments.
It's an interesting debate, of course, but it seems like it is purely academic.
And the Vatican is merely entering into the discussion from a moral perspective. And this does matter to Catholics who follow the teachings of the Church.
No one is saying 'ban it'.