They simply don't care because their customers don't care either. People like us who care about low distortion, jitter or high dynamic range are the minority
I feel like this is the unfortunate truth. I test so many audio products through Amazon Vine and most of them are terrible. Products designed for normal people have no real thought in Sonic capability. It is amazing how many Sound Bars which cost anywhere from $60 to $500 have terrible DACs with obvious artifacts and distortion even in uncontrolled settings.
I have heard some utterly astonishingly bad performance.
So many Bluetooth speakers have terrible performance as well, both from their BT chipsets as well as their DACs... Plugging in a decent dac via 3.5mm can make them sound totally different but typically defeats the purpose.
Considering there are such affordable standalone dacs on the market and the dac chip in this product costs under $10 in bulk (with all the ESS Q2M chips typically costing under $20 even in smaller bulk).
Every product could have something close to Sonic perfection if they actually cared. Most products don't get near 90 SINAD... Nevermind anything higher than that.
The sad part is that some of these devices actually have good DAC chips in them but they don't bother to implement them properly so the performance is still atrocious.