Would it be up to the suits, rather than the writer or the director? Would they really market test for something like that?
The least likely explanation is that the character detail was chosen based on principle.
Would it have been better if it were? Anything that comes across as preachy would turn an audience off.
It's doubtful that they made the movie to make a pro-life point. But the fact that somebody in Hollywood feels and acknowledges ambivalence about abortion could be a good sign.
If Roe v. Wade is ever overturned it will be because of women like the one in this film, IMO. This is 100% a women’s issue and it’s based on feeligs, not on logic or morality. (haven’t seen the film, BTW - not a Hoffman fan)
Since angst over abortion is contrary to Hollywood's reflexive thinking, my guess is that it would have taken a persuasive bit of evidence from marketing to nudge them in that direction.
The point of good art is to illuminate a principle without becoming preachy about it.