TDP doesn't tell you what the actual power consumption in practice will be. It is defined in some weird ways (different between manufacturers), and generally not intuitive. I would recommend to avoid trying to read too much into the TDP, wait for actual measurements of power consumption.
My understanding is that typically the TDP is designed to fit to the base clock of the processor, and doesn't necessarily include the amount of power necessary to achieve the boost clocks.
Anandtech do a deep dive on how Intel calculate TDP numbers [0]. It's complicated (and completely different from AMD, so never try to compare numbers).
Interesting, thanks! From that article, Intel's TDP is roughly equal to the power draw during full load on base frequency. How does AMD define it then?
I've read some in-depth analysis of AMD's calculation somewhere too, but I forget where. I do remember that the TDP numbers on AMD are closer to maximum power draw.
Never investigated GPUs. One way to find out would be to trawl Anandtech reviews and collect TDP and measured power draw numbers, they always take measurements.
My understanding is that typically the TDP is designed to fit to the base clock of the processor, and doesn't necessarily include the amount of power necessary to achieve the boost clocks.