Talk time, browsing time and video watch time are even worse than technical specs, because they're heavily dependent on specifics of particular use cases. Is it "time watching Netflix" or "time watching YouTube" as tested by C-suites' kids? Or "time watching a video on our optimized player under minimum brightness, no connection and all other measures of power optimization engaged"?
The thing is, I don't trust the vendor. They have every incentive to stretch and lie in their marketing copy, and they do that. And you can put any bullshit into self-selected "real use" metrics like "talk time", "browsing time" or "number of songs / photos that fit on the device", by choosing unrealistic values in some parameters that make the result look favorable. But you can't cheat much on raw GHz, mAh or GB. In the atmosphere of (experience-based) lack of trust, I prefer raw facts and making the necessary ballpark calculations myself, thank you.
("Number of songs / photos / movies that fit on the device" is one of the more annoying/dumber metrics ever. It's as if car companies gave you "number of cities you can round-trip through on full tank" instead of MPG or l/km values.)
Or, if the vendor insists on "real use" metrics, they should at least provide the math behind it, so that I know they're not pulled out of the asses of people in marketing department. The core problem is, still, that I have experience-based (and market-understanding-based) bias against trusting what a vendor says at face value.
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RE washing machines, don't confuse engineering numbers on the interface with use cases (the "technical specs" of a product) and the engineering numbers for internals. I don't give a damn what kind of motor you put inside, much like I don't give a damn what particular CPU you put in a mobile phone. The motor turns, and apparently has enough power and torque to drive a loaded machine to stated speeds; all I need to know now is how much power it (or rather, the whole machine) eats and how noisy it is. With phones, the CPU is ARM and runs Android; there's little user-facing difference between various SoC models, so all I care is how much cores it has and how fast are they.
(And yeah, I actually might be interested in the materials used in the internals of my washing machine, as a proxy for its reliability; however, given how hard it is to find reliable white goods these days, I just don't bother - I assume they're made out of costs saving and super glue, and plan accordingly.)