The reason Google got where it did is that the competition were nowhere near. Nothing to do with Apple and any agreements.
I've tried at least Yahoo!, WebCrawler, Lycos, AltaVista, Ask Jeeves, Yandex, Inktomi and AllTheWeb, as well as Bing and Ecosia. For a while, AltaVista was a clear winner.
Then we went through unfathomable merging of results and company ownerships. And being totally inundated by paid results and adverts.
And have now ended up using DuckDuckGo by default, for most things. The country option is quite helpful. But for some reason have Ecosia as default on one instance of Safari.
Have to switch to Google for some purposes - especially one site I use that has its own appalling within-site search service. So I use the site:xxx.yyy.com option and get quite good search (ineffective in DuckDuckGo for my purposes). And for broad-brush shopping, nothing else gets near Google. Though I never buy through those searches - they are always "I wonder if anyone sells..." queries.
But all search these days seems far too soft - it thinks it knows best. If I want to search for "Jhon", there is often a particular reason I don't want results for "John".