Those aren’t spinners (also called numeric updowns, see [1]). Those are throbbers (also called loading icons, see [2]).
Hah, I did not expect that. I can't imagine any end users will be able to name that one.
Anecdotally, I’ve only ever heard non-frontend developers call them “spinners”.
Maybe starting a discussion on the articles’ talk page could elicit some change? Language evolves, after all.
Such as these non-frontend devs?
https://learn.microsoft.com/en-us/previous-versions/windows/...
I think they fell out of fashion after the scroll wheel was invented