I'm not talking about "more FLOPs at max pinned wattage", that would be Intel. I'm talking about efficiency as in performance delivered per watt used and on that metric Ryzen has Intel beat on desktop.
So it stands to reason those new Ryzen chips would also perform very well in laptops.
No, you’re misreading what I said. My point was that the metric AMD has Intel beat in is “performance per watt under load”. With Ryzen, each watt you spend will get you more FLOPs than the same marginal watt will get you on an Intel chip. It’s like Ryzen is a car with more torque, that can turn each cc of gasoline burned into more force, and so get you further down the road. But that doesn’t mean that Ryzen idles as low as an Intel chip; i.e. that the Ryzen car would end up burning less gasoline over an hour of city driving.
Ryzen can be more power-efficient in e.g. a server (constant near-100% load profile) while also being less power-efficient in a laptop (constant near-idle load profile.) People who talk about the Ryzen power efficiency numbers are only talking about how it performs in the server-like test context (or, often, a gaming context, where the measurement they’re using is just “what sort of PSU do you need to power this thing at max load.”) As is evidenced by sibling posts in this thread, Ryzen doesn’t fare so well in the laptop-like test context in practice.
So it stands to reason those new Ryzen chips would also perform very well in laptops.
[0] https://www.tomshardware.com/reviews/amd-ryzen-9_3900x-vs-in...