Shake to undo is Voice Control's little brother.
That. When I need it, I'm really glad it's there. But I go days or weeks without using it.I use it very rarely. But there have been a few times where it was needed.
I've owned iphones since 2007 and I've never used this. Honestly I didn't even know it was a feature until now. Sometimes the undo typing box would come up but I never knew you had to shake the phone for it.