Well, I don't believe that the fetus is a person, but this is a personal belief. There are other beliefs. That's not the problem.

Here's the problem: the so-called conservatives on the Supreme Court don't believe the fetus is a person either (though they rely on that belief by so-called evangelicals in order to advance their agenda).

The Reagan-Bush-Trump Supreme Court believes that a corporation is (i.e. has the supreme rights of) a person, and that a state like Mississippi is (i.e. has the supreme rights of) a person.

Given the bent of the majority of the present "Supreme" Court, actual persons (whether fetuses or pregnant women) have relatively little standing.