But that was my entire point (root thread comment.)

It's not that Apple was taking existing Intel CPUs and designing bad thermal solutions around them. It's that Apple was designing hardware first, three years in advance of production; showing that hardware design and its thermal envelope to Intel; and then asking Intel to align their own mobile CPU roadmap, to produce mobile chips for Apple that would work well within said thermal envelope.

And then Intel was coming back 2.5 years later, at hardware integration time, with... basically their desktop chips but with more sleep states. No efficiency cores, no lower base-clocks, no power-draw-lowering IP cores (e.g. acceleration of video-codecs), no anything that we today would expect "a good mobile CPU" to be based around. Not even in the Atom.

Apple already knew exactly what they wanted in a mobile CPU — they built them themselves, for their phones. They likely tried to tell Intel at various points exactly what features of their iPhone SoCs they wanted Intel to "borrow" into the mobile chips they were making. But Intel just couldn't do it — at least, not at the time. (It took Intel until 2022 to put out a CPU with E-cores.)

Intel for the last 10 years has been saying “if your CPU isn't 100c then theres performance on the table”.

They also drastically underplayed TDP compared to, say, AMD, by taking the average TDP with frequency scaling taken into consideration.

I can easily see Intel marketing to Apple that their CPUs would be fine with 10w of cooling with Intel knowing that that they wont perform as well, and Apple thinking that there will be a generational improvement on thermal efficiency.