Nah, do not think there is such mechanism in Macosx, also I migrated from M2 and 2 days passed - I think they just did not implemented it for M3 Air yet in official Sonoma 14.4.1, or anyone can confirm that it works on their MBA M3?
Just now I updated to BETA 14.5 Sonoma, and LPM works straight away.
Results in Geekbench6 LPM, I got 5-6c lower temps:
13" MBA 8-core M3 Score: 1690/5000
https://browser.geekbench.com/v6/cpu/5886588
13" MBP 8-core M2 Score: 1500/5500
https://browser.geekbench.com/v6/cpu/5886589
Wanted lower temps when using it in lap, but MBP 13 M2, and especially M1 is still significantly cooler than MBA M3 13 (fans do not run on pro either, but it is cooler 5-10c). Also MBA screen gets hot at bottom a bit, unpleasant.