I can agree with your adept evaluation to an extent. here are my arguements mostly backed up by examples in just about all long standing products (Cars, Microwaves, Stoves, Fridges, Washers & Dryers, Computers - not so much desktops so much anymore but laptops with DVD media of any kind).
The UK has reach saturation over some 12mths ago ... and smartphone sales are STILL increasing ... churn is a bit higher, but upgrades from existing+continuing customers are growing higher than the churn, thus revenues & profits are not affected. I'm talking UK, Isle of Man, China, and Japan. Yes the race to the bottom is already happening and currently the best way providers - still the key holders - can do this is by contracts, is holding up. Over time economies of scale will remain the reason hardware companies stay in business.
Now the part that has a huge hole in your analysis - which is VERY astoute and valid - is my counter point which also is valid:
Cars ... over the past 100yrs have increased in price exponentially REGARDLESS of how many ppl purchase/own/insure or drive them now vs then.
Washers/Dryers/Vacuum Cleaners ... again the same deal in the same time frame.
Fridges/Stoves/Microwaves (the latter I'm reaching for here but premium models do fit with my analysis & point).
Computers (mostly laptops with external storage media drives built-in: CD/DVD/BluRay/etc) in the past 3 decades.
Now of ALL the products, Computers are an exception which I'll get too, over the past 100yrs or VERY VERY close have ALL increased in prices!! Cars still get you from point A to B, consume some type of fuel, and still seat at least 2 ppl. Washers/Dryers/Vacuums still wash clothes, still dry them, and still suck up dirt like a dirty female phys-ed teacher in porky's ... well you get the idea. Fridges & Stoves still store food in cold temperatures, and cook our food.
So what has changed to allow these products to continue to sell at HIGHER $$Prices over such a short time EVEN though ECONOMIES of SCALE should determine cheaper costs and cheaper pricing to consumers while offering equal value?! Product Cycle changes, not entirely. Think about this here. Features, and their evolution of what they do:
Cars ... do what they do FASTER, SAFER, and with ever changing style. Quality Materials are used, and with colour & marketing do what they can.
Washers/Dryers/Vacuum cleaners ... well just about the same here: Dyson revolutionized Vacuum cleaners & now hand dryers. Washers & Dryers do so with LESS water & LESS electrical power spent and with better volume in design and colour now (who the HELL needs RED washer/dryers (?!) well my wife does, but we have nothing RED in our apartment so that puts a stop to that: also the $1500 price tag for both as well).
Fridges & Stoves; same deal here ... though Fridges/Freezers now make ice cubes (70's), and serve as air conditioners when you open them

and stoves have better designs, are made for wheelchair accessible, and safer gas stoves, better flat panel designs, etc etc etc.
The differences are Microwaves. The offer better features similar to the trends I've mentioned above, while offering pretty much the same price tags, ONLY the premium models which now envelopes the larger cu ft sizes increase in pricing. Computers ... original for the consumer market cost in excess of $10K dollars for a desktop with garbage power and single purpose use; I know because I was a kid then - Tandy, Radio Shack Tandy brands, Apple IIc's etc. Then as they evolved continue to offer more features, run more complex software and have newer more advanced chips! The desktops have reduced in price significantly but have now hovered for retail above $500 retail for decent modern average user specs, and anything capable of holding serious graphics cards and multiple multi-core CPU's for Gaming, Video Encode/Decode for High Def (beyond 1080P), or full Audio Production suits (not GarageBand mavens) are above the $1500 mark. Laptops though have increased significantly in price with burnable media as previously mentioned.
My Point .... pricing will fluctuate as the products evolve and offer more features: higher resolution displays, camera lens', better camera/corder software, more network capabilities - with faster WWAN (LTE) coming, and etc etc etc. How will retail pricing grow to the end users be acceptable? Marketing.
Apple is doing a phenomenal job at this, and although on paper you'd think they where CRAZY - looking at spec's, then looking at prices - you'd be right! And sorry but they're changing the marketplace by being crazy.
Nokia's SERIOUS problem is two fold: Lack of internal communication throughout ALL departments on real-time, and their lies which is seen through the industry and consumers. Just 4 weeks ago Olli-Pekka was voiced & vindicated that he'd hold top dog status and boom the board of directors sought other wise in quick haste. More internal communication does just benefits the brass, but the end users as well when engineers are not held back on submitting great hardware and not be under-minded by retail/marketing division's limitations, and or designers looking for small size. Once that is out of the way everything else falls into place: OS Strategy, software market strategy, marketing of software/devices/services, etc etc.