To me, it’s not so much about cutting off support as it is about directly harming the fetus which does not fall into the bodily autonomy category anymore. However, if the afformationed support was temporary, denying it would otherwise result in death and you knew it could possibly happen, then yes.

Yes, it does actually reduce abortions drastically. Harm to women can occur in legal abortions as well and if abortions go down overall, the risk of harm by unsafe abortions pretty much balances out the risk of many more safe abortions. Not to speak of the fetus. Harm done to them is also important and thereby gets reduced.