∆ plus the video is xeetechcare. Let's just take the findings with more that a heaped teaspoon of salt ...
Battery test results can have a big variance depending on what type of tests are carried out.
Obviously 7+ will lose out to s8+ in video playback due to the amoled screen. But if it web browsing then 7+ will not lose out.
As long as the phone can last a full day active use then that's good enough battery life. I think s8 or s8+ have no problem doing that.