Pretty sure the answer is use power-profiles-daemon as this guide for Ubuntu says:
For Framework Laptop 13 AMD Ryzen™ 7040 Series configurations, you will absolutely want to use power-profiles-daemon for the absolute best experience. Do NOT use TLP. Without getting too detailed, there are things happening behind the scenes that require PPD for the best experience for our Linux customers.
https://knowledgebase.frame.work/en_us/optimizing-ubuntu-battery-life-Sye_48Lg3
Given that this guide applies to Ubuntu I'm going to assume it likely applies to Debian as well? Does the PPD for AMD platforms recommendation apply to all Linux distros (not just Ubuntu)?
Still £127.99 in the UK :(