>>Huh? How do you expect Apple to show live search results if they don't send what you're typing to their servers?

I don't want spotlight to show any online results in the first place, is there anyone here who does?

Settings -> Spotlight -> Turn off everything you don't want. The first few times you open it it even tells you this.

Admittedly I haven't confirmed that this results in no API calls in the latest few macOS releases but it definitely used to stop them, at least a few years ago.