WTF? Mostly you can't even use consumer technology from "decades" ago - it's incompatible.

In 2005 the average size of a TV was 30 inches. Two decades ago a TV had no HDMI, and it only received analog NTSC or PAL.

A phone was 2G - 3G was the thing about to be but mostly not there yet. One decade ago the iPhone 5 was released.

An Apple iBook cost $1200 with 128MB of ram and a PPC processor: https://apple-history.com/ibook_mid_2002

Maybe a stereo is usable - although for midrange equipment the capacitors have probably dried out and you certainly won't be getting digital FM.

You would need to be very poor if you can't get working hand-me-downs from a decade ago.

My old gaming computer from 2013 still plays 2022 games on medium-high settings just fine. You can make computers run for a long time if you put in the effort.

Precisely, the users, by definition, care only about the user interface. The matmul machine can be hidden in any box, just that so far it has been tied in same box with the screen. Hence why the greater point is that thin clients are relevant if the user owns the matmul box.