Roe in and of itself did not do quite what you say.
It’s been quite a while since I read the decision, but if I remember correctly it:
prohibited states from interfering with abortion in the 1st trimester,
allowed states to put reasonable restrictions for the 2nd trimester,
allowed states to prohibit abortion entirely in the 3rd trimester.
While my memory may be off in these details, this is certainly a far cry from our present “abortion on demand up till the baby is halfway out” situation.
While I disagree with most of Roe, it did not cause the present situation, it just started the movement toward it.
The Blackmun Roe majority quite clearly, in the written opinion, admitted that if the “fetus” is a person, they are “of course” protected by the explicit requirements of the supreme law of our land, the Constitution.
And we all know quite well that the fetus is a person. “Fetus” is nothing more than the Latin word for offspring. Offspring of what? People, of course. It’s self-evident.