I cannot totally agree. From my experience, if the phone is wider than ~68mm, I cannot hold it firmly in my hand and operate it. The UI comes after that, for how far I can reach.
Same here :). But original Optimus has a screen in each key. This technically similar to a later design https://www.artlebedev.com/optimus/popularis/. Which also had a single big LCD and transparent keys on top of it.
I never knew him but as a daily Arch user, for a decade now, I am deeply saddened by this loss. Makes you think about how much you rely on people you never met.
It is no different from other products. There are people who do subjective reviews, and others who put some science in it.
Although, as far as I understand, headphones are both quite simple in engineering and complex with the task they try to handle.
Every person's audio perception is unique and depends on unique anatomy and unique experience (brain calculations). So it is quite difficult to normalize every data we can measure.
Still, some are trying to do it. E.g.
http://rtings.com/ - authors develop their methodology to take into account all relevant measurements, and explain their function
http://diyaudioheaven.wordpress.com/ - author does a measurement based subjective analysis of overall audio experience. Sometimes directly comparing rivals in relevant aspects.
https://www.reddit.com/r/oratory1990 - based on research from Harman R&D, measure and develops equalisation parameters for popular headphones, as well as, their weighted score (deviation from target)
The research is quite interesting in itself when addressing you statement, because it develops a statistical model of preference for audio reproduction by average human. Of course, it is not a silver bullet equal for all but many agree they enjoy headphones with "target" frequency response more.