The answer to "How were people able to afford the technology of the 80s and 90s that were made in developed countries" is that many of them were not able to afford that, and did not, especially in poorer countries.

The number of households having such devices was much lower, in large part because of the cost; devices such as home computers, laptops and smartphones changed the world not when they were invented but when they became cheap enough to be really widespread; when you could buy a Japan VCR or USA computer without having Japan or USA levels of income, which the vast majority of global population don't. If we lose the bottom of the market with the cheap smartphones, well, then hundreds of millions of people worldwide would not have smartphones.

Yeah, but no.

A VCR was pretty much ubiquitous. A home computer was not, in most part not because of cost but because of not being able to see the point. Smartphones are more expensive than they've ever been. If you buy cheapo you're buying something a few years old and terrible.

There was no lack of them in other countries, what has changed is the number of countries able to afford consumerism at all.

Are you comparing like with like? No. The hundreds of millions of people worldwide buying cheap are NOT buying Apple or Sony either, are they? They're buying the brands that aren't even in first world countries.

No shareholder will agree to cut profits. The price of sustainability will be tacked on top of existing profit margins, as it is in all products where it is relevant. Like all sustainable products, it will be available only to those X% income levels who can afford to pay the premium on sustainable products.

I wasn’t old enough at the time to remember the relative pricing of those things as a consumer, but things like walkmans, televisions, and IBM laptops seemed much more affluent then compared to now.

Sony themselves were perhaps. There were plenty lower down the market made in Japan brands though, such as Aiwa, Akai, Sharp and dozens of others.

A TV was a cheap almost commodity thing when CRT based by the 80s. Only the arrival of widescreen CRT and flat screens that pushed the prices into the absurd. I imagine the 60s and 70s was the era for TV prices to be dropping.

Sure there's been a little inflation and price rises too. Overall the switch to China hasn't benefited first world consumers from price benefits from the brands. The price benefits have been in places like Primark with a £1 T shirt and the unknown brands on Amazon marketplace. A pair of Levis or an Apple device is just as "for the affluent" as they've ever been. Often more so, despite manufacture moving somewhere cheap.