> If you’re lucky and leave enough extra space then you can design next generation parts to line up neatly with the thermal solution of last gen, then cap it at the limit of whatever last gen was designed for.

The mobile Ryzen 3/5/7/9 processors from the current year have a configurable TDP up to the same max (54W) as the earliest Ryzen "H" processors from 2017. The first generation mobile Core i7 from 2009 had a TDP up to 55W. The mobile Pentium 4 from 2003 had a TDP up to 76W (which appears to be the high water mark). In any given generation there were also lower end models using less power across a power range that seems to be fairly consistent over time.

Why does the thermal solution need to be redesigned if the heat output hasn't materially changed in decades?