It seems others have observed the same behavior:

https://discussions.apple.com/thread/254001650

https://discussions.apple.com/thread/253870288

I couldn’t get mine to type, or even suggest, the word after typing it manually multiple times.

Might be related to the EN-US keyboard having a big group of sequential letters on the top row: “ortio” are all up there, so there’s a very high amount of uncertainty? The swipe pattern doubles back on itself, makes it more ambiguous still.

I bet there are other words following that pattern which are ranked lowly until it shows up in your “actually typed” dictionary.

There’s a number of words like this that won’t autocomplete unless it’s seen it first.

Another one: condom.

My partner's QuickPath (swipe) keyboard on her iPhone would type the word "abortion" just fine, but mine would not. We guessed that it's because she's typed the word before and I hadn't. A small test seemed to prove that right. I found this surprising, but maybe it's old news to everyone else.

Worked for me first time. I think most people using the swipe keyboard are not as methodical as it requires you to be. You have to hover over the letters one at a time in order for it to recognize, rather than make a very fast sweeping gesture as seen in the video.

Abortion just worked for me.

And I don’t think I’ve ever typed it before on my iPhone.