My 2019 16' MacBook pro does about 2 hours of battery with only 488 battery cycles. i9 processor with AMD Radeon Pro 5500M. I'm just doing the most basic dev stuff. Generally a Chrome instance with ~20 tabs, VSC, and a Next.js process. I can't use it on my lap too long, it's hot. The fan never stops. Sometimes I look in the activity monitor to see why, but it's never something specific. A chrome tab using too much CPU or something. It's been the fastest self-depreciating machine I've used.

I recently switched to a M2 Air for personal laptop. Same exact workflow and tools results in zero heat, and the battery can do a few evenings of coding without needing to be charged. It's a gamechanger.

if it's 2 hours that's almost certainly gonna be one of the Intel macbooks, and probably several years old at that. The new Apple Silicon ones have batteries running for many times that easily.