"In our battery test, which tasks a tablet with endlessly surfing the web via Wi-Fi with its screen brightness set to 150 nits, the Surface Pro 8 barely lasted 9 hours and 6 minutes" - fair enough, but is "endlessly surfing the web" how most people actually use their laptops and tablets? And I know brightness is a tricky area, but do we know what 150 nits actually looks like in real terms?
I think too much emphasis is placed on battery life. We all know that in most cases you're never going to get the longevity that manufacturers suggest, but for me as long as you can hit 8-9 hours or so it's highly likely to be enough for the vast majority of people to get them through the day. More important for me is how long a recharge takes, during a lunch hour perhaps. But then most people are not likely to be using the device away from a power source for 9 hours in any event.