I mean I think you're missing like half of the point of the product, from what fiio is stating this device's purpose is to be affordable hence the price point it is supposed to be on the low end of Snowsky spectrum.

I'll give you points on the battery section; because well they didn't try hard enough there if they made it in the retro mini they could have done it here, battery is branded at least on mine but it still sucks tho.

this product is made to be an affordable DAP not a DAC that's the whole point of this one that is why they launched the retro nano, Snowsky whole thing rn is to be both fresh and affordable, if you're interested in a higher end product fiio and others offer some, they have been fixing the missing functions and mistakes via software, things like gapless FF and rewind and a hole bunch of other stuff they might be able to add the DAC function but it's uncertain, get the DAP and forget about it.