To posit that abortion is somehow permitted, one must completely reject the psak of Rav Moshe as illegitimate
We have rules of psak.
In cases of pikuach nefesh and murder, we are adjured to follow the viewpoint of the rabbi who rules in favor of life (in favor of saving a life and not ending it), even if it is one rabbinical personage over 10 greater rabbis, provided that the rabbi’s viewpoint is considered legitimate.That is even on the assumption the opinions are of equal weight which-with regards to abortion issues is dubious
Also, the writer chose to completely ignore that Rav Joseph B. Soloveitchik were concerned for the Rambam’s view that abortion is murder and paskened accordingly
Iirc the Lubavitcher Rebbe advocated banning abortion on demand completely
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