I will assume good faith and say you're not trolling, since it's hard to tell on the internet nowadays.
It isn't simply banning abortions that prevents abortions from occurring. A social movement that fosters dialogue and education about the moral status of the newborn is a precondition for any social development on the issue.
Why do you think women get abortions? Do you think abortion is something women want to have? Do you think they are thinking of it as a moral issue, "it is morally right for me to terminate the pregnancy because of bodily autonomy"? Or do you think women get abortions because of reasons like unexpected pregnancies (rape or otherwise), a fatal defect detected in the child, complication that risks their own life, etc...?
Also, the article indicates that the abortion rate doesn't skyrocket after banning it, so there's no utilitarian argument to be made here.
Yes, abortions are performed regardless of whether it is legal or not. Would you agree, then, that, regardless of your personal feeling on them, abortions are a necessary service/scenario for some women that will be present in society regardless of legal status? Because the article shows that that is the case, it will happen regardless of "moral education" just as there will always be people that need insulin.
So, following your claim of utilitarianism earlier, this means we shouldn't ban it as using resources to ban it does not provide any utilitarian benefit, to say nothing of the negative effects. In the same way that banning insulin wouldn't change its consumption, just drive the purchase of it underground where it is more dangerous and less regulated, banning abortion indisputably leads to dangerous, underground uses of a service that is consistently needed.
Following the above two paragraphs, It follows, then, that banning certain services that are consistently needed, such as insulin drugs or abortions, only leads to more issues that are not beneficial to anyone. Given that these services will always be needed in one form or another, it makes sense that rather than banning those services we instead provide said services in a safe, controlled environment. Even better would be to work on services and policies that would make the need for those other services not as necessary, for example work on sex education, healthcare, condom distribution, etc... have all shown to lower pregnancies and abortions.
And before you say "you're saying the government should hand out drugs and make everyone addicted and that's morally wrong", yes it is, which is why regulating things that are inevitably going to happen tend to work out. As counterintuitive as it feels, needle exchanges work towards lowering drug usage and healthier people.