5-6 hours? In 2025? That's... really bad. My 5 year old Macbook Pro lowest-spec M1 gets at least 10-12 hours of work on a charge and lasts for weeks in sleep mode.
I love my Framework but the battery life is indeed horrendous no matter how you slice it. Combine it with the sleep drain and if I use it for a bit then close it overnight without shutting it down it's probably dead by the morning.
To me it appears that the screen is a huge power hog - at least in the 16.
My idle power consumption at 0% display brightness is around 7.5W, but I've seen people get to as low as 6.5W. Not great, not terrible. With the display at 50% it jumps to the teens(13-17W).