DxOMark has started evaluating smartphone battery life, and the Galaxy S21 Ultra has fared poorly. The Exynos 2100 version languishes near the bottom of DxOMark's battery leaderboard, but the overall score is more than just a measure of battery life.
https://www.notebookcheck.net/Samsung-Galaxy-S21-Ultra-with-an-Exynos-2100-SoC-sinks-in-DxOMark-s-new-battery.539451.0.html
Oh please more bias. My sister has the iPhone 12 Pro max and my s21 ultra outperforms it. Not by much but its still there. How much did apple pay you?