I suspect this is all about Siri. They went from being top of the game in personal assistants to being a second stringer. Apple can't compete with Google Assistant without the data set and analytics. Personal assistants and web search are two sides of the same coin.

There are reports that right now Applebot is being used to scrape the content used by Siri. If youre already scraping the web, indexing it and building search and analytics services on top of it for Siri, user facing search is just a short step to take.