First, it is misleading to say our results just come from Bing. That's far from the case in actuality. Please see https://news.ycombinator.com/item?id=31490994 for a more detailed explanation on that.
On other search engines, they all rely somewhat on either Google's or Bing's web crawling: Qwant, Bing and Brave, Google (and Bing for images). This is easy to see as a webmaster since you don't see their crawlers much (if at all). Only Google and Bing are doing full scale web crawls. However, search is a lot more than traditional web links -- in fact it is about half now from instant answers that can come from dozens of sources and indexes (which the above comment gets into).
On other search engines, they all rely somewhat on either Google's or Bing's web crawling: Qwant, Bing and Brave, Google (and Bing for images). This is easy to see as a webmaster since you don't see their crawlers much (if at all). Only Google and Bing are doing full scale web crawls. However, search is a lot more than traditional web links -- in fact it is about half now from instant answers that can come from dozens of sources and indexes (which the above comment gets into).