Well that is obviously not true. They need to have the index in order to serve up AI. And it's not 100% of all of the searches that are done without any search

Well that is obviously not true. They need to have the index in order to serve up AI. And it's not 100% of all of the searches that are done without any search results. Remember also that the fact that there is an AI response on a particular search does not mean that it's enough. People might still click on a link. There is a reason why Google has chosen not to remove fully their search product and replace it with only an AI bot.