A newcomer can index, store, search and display data differently, but first they still have to get that data. Which means dealing with JavaScript, paywalls and other fun stuff like that.
Besides, regardless of what you do, you would need to have tons of storage, bandwidth, CPU power and a high-availability infrastructure.
The vast majority of the data on the internet is dross or spam, if someone finds a way to index only quality content, the crawling burden could be radically smaller.
I remember DDG did side-by-side comparisons, but did they ever just query Google themselves and then do their own stuff on top? Anyway I'm not sure Google can be beaten at all by any particular newcomer, instead they might suffer death by a thousand cuts as more niche engines like Shodan show up and bring in context-specific searches that are orders of magnitude better than Google's more complicated all-web-they-approve-of-and-find-relevant-to-your-account search.
