My linux laptop (32GB ram / beefy gpu) barely withstand 40 min on battery, but can handle very daunting tasks, and obviously gaming.
These are 2 different use cases, but right now, for the ultra portable laptop, Air is the king, until x64 brings back the efficiency per watt. Even qcom can't compete. That being said, I am a big fan of the apple hardware and not the apple software, so whenever Asahi linux is ready enough (with good battery life), I am definitely jumping ship.