for dumb tech no-name is fine, we have that stuff figured out to the point where you can kick it around a bit without it breaking. But high-tech is weirdly robust and fragile at the same time. You can cheap out on the circuitry and you'll be fine for a while but eventually the low grade circuits around the chipp will damage it, causing it to lose performance. With bigger price gaps you usually get some reduced performance in a key part on top of it (usually memory or the processor) if it goes even beyond that then we enter the territory of "this device would be selling at a loss if they truly ship what's wrotten in the specs, where tf do they get the money to compensate for that?" (spoier: it's either spyware and selling customer data or lying about specs)

Obviously there are exceptions here, most high-end tech products for example are vastly overpriced to generate as much money as possible from whale customers. But with the mis- to low-high-end stuff you usually fall on your face with some aspect or another after a few years with cheap no-name devices.

Not to mention the very real problem of credibillity: it's very easy for unknown players to just fake reviews of their products, you won't ever know because there are not enough real users of these devices to punch through the fake reviews