Perfect timing! I am auditioning Ethernet cables as we speak, and without a doubt I hear a difference. I was a software engineer for thirty five years with much of my time spent working on operating systems or at the device level. I understand well how and why data networks and protocols function, designed a few myself. But all bets are off when you start using an industrial technology in the delicate and sensitive world of high end audio.
Let me ask you this, why did they need to change the Ethernet cable specification so drastically between cat 6 and cat 8? More shielding, metal termination connected to shielding, grounding, more twists in the pairs. Noise and interference. And these are what affects your audio system, even when the data arrives 100% intact.
Feel free to continue your willful ignorance, but most of us know that everything matters.