[immibis]

Laptops could do with the power use reduction.

[umanwizard]

I think you are underestimating how many times slower processors would be without any speculation at all. It would mean having to wait dozens of cycles on every branch so you can know whether it was taken before executing the next instruction, for example.

[epcoa]

Speculative execution like almost every modern CPU performance trick decreases power use.

Mobile SoCs have OOO.