Perf per watt isn’t interesting to users who want the job finished. Work done per joule is extremely interesting but Intel is near the top of the game on that metric. Many CPUs that are viewed as low power are not energy efficient.
On an energy basis the “performance” cores in an Intel CPU are more efficient than the “efficiency” cores.
TDP and actual power draw are two VERY different things. Intel and AMD both will plaster 95W or 125W or 160W TDPs on chips that will draw well over 250W when boosting as long as your cooling allows for it.
