A demanding game on a macbook air m2 will still draw close to 30 watts and while that is actually still good for a laptop relative to what the output is, and you can probably do things to improve that by tweaking in game settings, it’s still going to suck power out of a 50Whr battery.
Steamdecks also run an efficient ryzen apu that lets them play games for 2-8 hours depending on how things are tweaked. Likewise on my 39Whr ryzen thinkpad(intel got a 59whr battery dont get me started on that nonsense) I can get 8-12 hours depending on usage normal browsing as well.
This isnt to take down the m1 & m2. They are definitively more powerful, theyre definitively more efficient, I’m not disputing that. But the gap isnt as huge as it was when the m1 launched.