Apple could've made a very bold statement against Google's privacy and tracking activities by going with a more privacy-friendly search engine (like DuckDuckGo) as the default.
But Apple's not actually interested in that. They're interested in making money, a lot of it. And they're very good at it. You don't become really really good at making great big gigantic piles of profit by taking your eye off the prize with silly for-show antics like endorsing an also-ran. You partner with other giants. That's how it works.
Don't pay attention to Apple's glitter-throwing, pay attention to what they actually do, and the partners they keep. Business first.