Media consumption - even there, the better screen which has richer colours. i.e. it covers the P3 colour gamut will make a difference for videos or photos that is recorded in the higher gamut.Oh really ? Where did you use the new one ?
I use the laptop for media consumption and browsing and it works great. If the reviews show massive improvements i can always exchange it.
Browsing - browsing heavy websites with lots of javascript, the M1 will be faster by a significant margin
Battery life in both situation is also much better on the M1. Like I said, the only real reason to choose the old model is if you want to run Windows software.
Anyone who has a chance to do an exchange (and doesn't run bootcamp or virtualise windows) should do it.