Anecdotally, I've been able to use my M2 Max MacBook Pro for 12 hours straight with 50% battery at the end of the day. Nothing intensive, just Chrome, Emacs, Spotify, Slack, Discord, etc.
My 14" M1 Pro rarely got more than 7 hours and my former work 16" M1 Pro more than 9 on a React workflow. When introducing VM work or anything fairly heavy to the mix take 2 hours off each. Typically at 50-60% brightness, have iStat showing load so I can catch any errant processes.
My biggest issue with this release is no published improvements in battery life. 22 hrs is for movie watching. Wireless web - of course very low load - is still 15 for the 16" and 12 for the 14", same as M2 Pro which is each just 1 hour more than the M1 Pro.
I almost never touch the brightness. It does what it wants. Not sure. Looks like it's at about 1/3 right now, but it'd be brighter if it weren't kinda cloudy here, I bet.
Program choices matter a lot. I gained about 30% battery life switching from Chrome to Safari, years back. I do have Teams and MS Outlook running all the time on that machine though, and they're not exactly slim.
