No, it's not. AI mode is something you have to select (in the search window). There is an AI overview provided with your basic search results.
That's what I get, in the UK, logged out of Google, from a search in Firefox omnibar using "Google" as provider.
I'm aware that they have other things that can be described as AI modes.
AI Mode in that screenshot is the tab to the left of All.
No, it's not. AI mode is something you have to select (in the search window). There is an AI overview provided with your basic search results.