Absolutely. And turning off Siri's "Learn from this app" should not require the user to navigate to every single app's menu, when Siri has a top level page in Settings.
The division of per-app vs app list in general is bad.
I think they should just throw in the towel and duplicate settings. Meaning, we can turn off Siri learning from an app or from the Siri page. Or we can turn off banners from the app or the notifications page.