The long term emotional impact of abortion seems like it depends a lot more on the person and context than miscarriage, which is universally awful.
However, you always have to be careful with statistical measures like this, it's certain to have been a traumatic experience for some fraction of women experiencing it, no matter how small. For people in that position hearing 'oh, it's no big deal' must be pretty hard.
Now, there are people who very much want that not to be true for political reasons, but wanting something to be true for political reasons doesn't make it true.
That can't be right, you're dearly underestimating the number of miscarriages or we live in a very crazy world.