Here's a pretty good comparison between the latest Dell XPS 13 and latest MacBook Air with specifications, benchmarks and evaluation (without judging operating systems).
Tom's Guide said:MacBook Air 2020 vs Dell XPS 13 2020: Which laptop wins?
... The MacBook Air 2020 shows that Apple's willing to adjust to user feedback, fixing its keyboard and lowering the starting price. Only time will tell if Apple will give its MacBook Air U-series processors, or if it will reserve them for the MacBook Pros. But with just the right mix of performance and price, the MacBook Air 2020 is the best MacBook for most people.
Meanwhile, the Dell XPS 13 is like Omar from The Wire: the king of the game. The InfinityEdge display is killer, its 1080p battery life is phenomenal and its keyboard makes for excellent typing.
As for the future? Apple is expected to release MacBooks with ARM processors, which could drive their battery test scores into the sky. But for now, the Dell XPS 13 2020 is the best ultraportable around.