That depends on how you define a human, and there’s the entirely separate issue of whether it being human or not should be the deciding factor. For example, a braindead human is still human but killing them is quite different from killing a healthy human. Oversimplifying the issue helps nobody.
We can agree on that (that this is the legislators’ reasoning). Whether it’s good or even valid reasoning remains to be seen. For one thing, the alternative to an adoption is one more parentless orphan - which is often also the alternative to an abortion. Oversimplifying the issue helps nobody. I’m not accusing you specifically of oversimplifying, as you made it clear that you were pointing out an oversimplification made by others.