This very much could have been my husband about a decade ago. The last tantrum my middle child ever threw, with lots of screaming and running and destroying things like a fucking tornado in the middle of a Target. Spouse carried them kicking and screaming out to the car while I finished checking out and by the time I got there they were buckled in their car seat, completely calm and composed, like a switch flipped. (As far as I know) it wasn't any sort of punishment or shining moment of parenting, the kid just decided, I'm done now.
And they haven't thrown a fit since.
They had just turned 4. I remember being really worried because they were starting preschool soon and they were such a demon, I was certain I'd be called on the first day and told they'd been expelled. Now they're in middle school and charming as anything.