Will pile in on the pricing discussion. I have no problem with Topping, SMSL, Benchmark, or anyone else charging whatever they want.
For me, though, there are just too many great options in the ~$300 range to pay much more for a DAC or Amp. You are paying for features you PROBABLY can live without, and you are paying for sound differences almost no human could discern in a proper A/B test. Basically you are paying for bragging rights and bling. Nothing, absolutely, nothing, wrong with that, but it isn’t necessary.
For DACs I am happy with my DX7s, D50s, and M500, and amps 789, Geshelli Archel 2 Pro, and JDS Atom. Will I ever upgrade any of these? Probably! But not at the the price points the A90 or the D90 are selling for. I don’t need or want them that badly. But that IS JUST ME and others can and most definitely will feel differently, and I am happy for them!