There is no doubt that a great streamer with an excellent D/A Converter plugged into a great amp will be very good.
But what if you spent more money on a fantastic amp with a top notch D/A convert built in and just a so so Streamer connected digitally to the amp.
Just curious what the forum thinks would be best?
I’m not sure there’s a simple answer to this. It’s a similar question if you substitute CD transport or player for the streamer. Then the question is how much better does a heavyweight player, say like a Luxman or Oppo, sound than an old Sony DVD player for a fraction of the price. Or a £299 player versus a £2,999 one!
With streamers, you are very much at the mercy of the interface and software/firmware updates. Aside from ergonomics and ongoing support from the manufacturer, other issues can crop up. For example, when the BBC decided to remove itself from the popular TuneIn platform, some users were left with no internet radio from the Beeb. Others were offered alternative platforms, such as Airable.
Another aspect is just how good the digital stream is. Yes, they’re still the same 1s and 0s. They aren’t faster or slower, or a different pitch! But they might be accompanied by unwanted noise which different receiving DACs will cope with in different ways. All somewhat unpredictable, and system specific.
Lastly, your underlying assumption is that a super-duper DAC automatically sounds better in some way than a merely super one. But it’s quite hard to say in what way in many situations, beyond a luxury chassis, or a striking display, or different filters. Or perhaps some obscure technical difference that one may not derive any benefit from other than a belief in the superior technology e,g. Millions of taps in a Chord FPGA.