Google immediately jumps to mind. The search result quality combined with the infrastructural investment required to execute on copying Google seems like it would take even an entity with no budget constraints more than 3 years, and that’s just search; Google also has maps, email, etc. Does your question assume any budget constraints? (I’ve been using DuckDuckGo as my default search engine for a few weeks and the results are obviously substantially worse than Google. And DDG has been trying pretty hard for over a decade, but with less than unlimited resources but still a lot.)
DuckDuckGo isn’t a big player but there are other companies with massive investment into search like Baidu and Microsoft.
There are some articles about Bing winning in blind tests against Google like https://www.neowin.net/news/microsoft-new-blind-test-shows-users-still-prefer-bings-results-over-googles/ .