That's the TDP of the chip, or the maximum amount of heat it can generate, not necessarily the power draw. Also, you were assuming it was running at full load 1

That's the TDP of the chip, or the maximum amount of heat it can generate, not necessarily the power draw. Also, you were assuming it was running at full load 100% of the time. I don't have a source, but for comparison I believe Apple's AX chips have a TDP of ~2-3 W.