AMD usually sets the marketing TDP to around 2/3 of the PPT (power target), e.g. 65 W CPUs have around 80-90 W PPT, 105 W CPUs around 140 W PPT.
Also, modern CPUs and GPUs pretty effectively throttle to the capacity of their cooling solution. I would not necessarily recommend it, but you could probably get by without any issue slapping a solution that reliably dissipates 65W of heat on any Ryzen, and have a stable computer. It would just happen to run up to its thermal limit regularly and clock down.
If you actually want a lower power/heat setup, you can undervolt and underclock the CPU and not worry about bouncing off the thermal limits.
Intel had products with TDP of 65w and 125w, so AMD "matched" that by making up a TDP formula to get the results they wanted. At the time, Intel's TDP was actually mostly accurate. It would turbo above that, but only for a few seconds before dropping to the TDP limit.
Then when AMD started winning, Intel had to get match them in return. If AMD's "125w TDP" parts could turbo forever, then why shouldn't Intel's? And so that's what they did. And just like that over a few generations TDP became entirely stupid & without a shred of meaning.
(Maybe I'm wrong, I thought the TDP figure is the maximum sustained power that has to be dissipated by the cooling setup, the CPU can output more heat briefly but over a long period of time it'll average 65 W assuming it's fully utilized?)