Delete Siri Suggestions in Safari on All Devices

Let's ask this question again. The question is, how to DELETE or CLEAR previous Siri Suggestions in Safari. This would be for all devices, but since I'm asking more for Mac OS, we'll start here. The question is not how to turn off the suggestions. That's easy.

Going to the History menu item and selecting Clear History doesn't do it. Or the same function under the Safari menu item. My guess is Safari on all devices has a secret cache of searches that's permanent and tied to iCloud, since the Safari (Siri) Suggestions is in the Search section of Preferences and these appear on all devices logged into the same iCloud account. I've ran Onyx and Cocktail to clear everything also. Short of a clean install I can't think of any other way.

For those that want to do the same, but haven't found a solution either, this is the best I can come up with:

To prevent any further websites from being added to the suggestions in Safari, in case I decide I want to reenable it, I went into System Settings->Siri, then I clicked Siri Suggestions & Privacy. Scrolled down the list of apps to Safari and unchecked both boxes. By doing that, it disables the Include Safari Suggestions checkbox in Safari Preferences.

Do the same on iOS. Settings->Siri & Search. Scroll down all the way to Safari and select that. Hit the two buttons under "In "Safari"" to turn Off (not Green). I personally left the Home Screen settings to On (Green).

Repeat for any other app you want Siri to not learn from. Haven't decided if I want to do that yet.

You'll need to do this for each Mac OS and iOS device. I doubt a complete erase and restore of an iOS device will accomplish this, but if you're willing to try it, then you can reply if you like.

With Apple being so privacy conscious, you'd think that this would be possible. Especially with Siri and the perception of privacy.