Firmware and kernel module updates (distro dependendent; e.g. Debian)
Kudos to AMD principal engineer Mario Limonciello for driving these changes across the board!
This is one advantage of increased competition (e.g. from the Apple M series); the entire ecosystem is pushed forward.
I am personally benefiting immensely from these improvements on my new Thinkpad t14s with AMD 7840U (battery life going from 4-5 hours to easily 10+ hours).
Finally we don't have to settle anymore for underwhelming battery life on Linux laptops :)
Yes. You should not use tlp anymore on any AMD processor that supports p-states. TLP does not support these and it's own logic may conflict with the CPU. Use PPD and let the processor itself take care of the optimizations!