If a pregnant woman that you know in real life would come to you and say that she's deciding to abort her baby because she thinks it has no right to use her body to live, how would you feel in that situation? My guess is that your first instinct would be to think she's a psychopath or going through a nervous-psychotic breakdown.
But it is normalized, just with other arguments than are used in these online debates. The arguments are probably not even verbalized, because people doing abortions would rather not think about what they are truly doing and just get over with it.
Now think if a person you know in real life would come to you and say that they're going to start killing people of a certain group. My strong guess is that you would think they are a psychopath or going through psychosis. Probably you'd call the police.
Yet, this is also normalized whenever the rulers want war. Look at how both sides are dehumanizing each other in the Ukraine conflict, in the most disgusting ways imaginable.
If that was the only reason she was aborting - and there were no mitigating factors such as early-stage accidental pregnancy or difficult life circumstances - then I might think that person selfish. But that's not what actually happens. Abortions by and large are wanted because a woman does not think they are in a good position to bring up a child in the world. Perhaps she had a one-night stand and the contraception failed. Perhaps there are abnormalities that will make the baby's life full of suffering and difficulty. The "no right to use her body" bit is not usually the sole reason for wanting the abortion, but it's the part that makes it ethically justifiable.
Exactly, because that argument is so far-fetched and cruel, that it's rarely seen outside of online debates. Having an abortion is still cruel, but there are always ways for people to do shameful things while putting their consciousness aside. It's probably rather easy for most.
I think your argument on the health of the baby (or mother) is more ethical than any "no right to use her body" argument. She was the person who decided to put the fetus in that situation.
To make a comparison, there are people arguing that the fate of prisoners in the German death camps during WWII was not really the Germans' fault because they didn't have enough food to feed themselves, much less war prisoners and other detainees. Which is inching quite close to the abortion arguments, especially if you reduce the victim to subhuman status. Hoping to show that this way of reasoning is misguided.
I don't find the German death camp analogy accurate or compelling; the Germans actively and deliberately herded up the Jews (and others) locked them up. This conscious intervention in the course of a living human being's life rendered responsibiloty onto the German state.
Have you heard of Judith Thompson's "famous violinist" thought experiment? [0] It neatly captures the idea of how a right to life oughtn't extend heavy legal responsibilities onto an individual. At least, most people would say that the main character has the right to say "no" to the situation.
[0] https://ethics.org.au/thought-experiment-the-famous-violinis...