Or, perhaps your Roon bridge and Intel Nuc is just fine and that your related hardware is helping things along.
Of course, it can be difficult to compare because it takes time to connect different devices so A/B is hard. But it could be that all is just fine with your system. Be grateful.
Be that as it may, your experience does not negate the experience of others.
Perhaps there is a way to help conceptualize why streamers can (not always) make a difference via a simple test most of us can do at home. Some will claim it’s an unfair test, to which i would reply I’m suggesting it only to illustrate the concept of why a clean and jitter free signal to a DAC is important - the function of a streamer.
Here’s the test: regardless of your streaming source (hi-end or not) try using a cheap analog RCA interconnect to the SPDIF input of your DAC. A digital spdif cable has an impedance (75 ohm) designed for digital transmission. But, the cheap RCA cable will transmit the digital information to your DAC - all the 1 and 0s that are supposed to be there will be there. Yet it won’t sound right. Why?
The impedance mismatch of the analog cable is causing a change in the slope of the voltage changes introducing jitter to the DAC.
Yes - not exactly the same thing as a streamer - but it does illustrate that 1s and 0s can be bit perfect yet not sound correct.
This test does not illustrate the significant efforts to eliminate noise taken by manufacturers of streaming devices.That too produces audible beneficial effects.