This is how they carried out their test:
[...]However, in our custom battery life test — where we set a phone's display to 150 nits and task the device to endlessly reload web pages over a cellular connection — the iPhone 14 Pro turned in a less than stellar result. Here's what we found.
That is not an accurate test of real-world usage. I wish these reviewers would stop this nonsense test and just use the phone like an average person would.