The parallels you’re trying to set up aren’t really parallel.
The murderer who murders and the robber who Rob’s weren’t raised in a society filled with millions of people who told them over and over again that murder or robbing was fine or even good, and also praised and comforted them after the act. A thief or a murderer knows from society, and from what is written on their heart by God, that what they are doing is wrong.
Abortion is a bit different. Society doesn’t have it’s head on right with this issue. And given the unique nature of the thing, it is (unlike regular murder), extremely easy to mislead a woman into believing she isn’t doing anything wrong, isn’t destroying an actual person. They have been led down a bad path, and unlike a murderer, they don’t have knowledge of the sin they are committing, which as we know is one of the requirements for a sin to be mortal.
Now there is a small sunset of women who will admit the thing in their womb is a human and will get an abortion anyway, but those sick people are by far the minority, and I’m sure they’ll have to answer for that in front of the throne of God, but in terms of lawful punishment, it would be nearly impossible to prove which has evil intent and which didn’t.
However, I havent met many prolife people who think the doctors who carry out the procedure should face no consequences, because unlike those women in the previous paragraph, they are specifically and rigorously licenced to understand biology, and so have no excuse. They know what they are doing.