You test efficiency with the applications you are using. If you are not going to render, there is no reason to care about efficiency when rendering, is there? If you are going to render, you are power limit the CPU to 160w where it's most efficient. No that hard is it?Yeah, more efficient because CPU load is far from 100%. That's how you cherry pick testing methods
Socket 1700: 2021
Socket AM4: 2017
Basically Alder Lake is hot as hell, has very poor software compatibility, requires ultra-expensive DDR5 to run properly and upgrade paths are abysmal.
Intel just sucks, admit it already
In 99% of productivity workloads the 12900k absolutely massacres zen 3 in both performance and efficiency. That's just a fact. Photoshop / premiere / transcoding/ export / solidworks / autocad and a bunchload of scienitific applications.
Also, no matter which socket you buy right now, you are going to get 1 upgrade for each, intel 12th gen and zen 3d, so that argument is just invalid either way.