Indeed, they are not really trying hard to hide it, even. In any of those reviews of ethernet switches or power conditioners, did the reviewers think to throw in a little confirmatory evidence?The biggest fraud in the industry in youtube channels and hifi papers AND dealers is that more expensive electronics is always better than less expensive. And you never see those cheap, good bargains like Aiyima a07 or Topping d10s reviewed by What Hifi. I guess its all about advertising.
Like "oh, I noticed my Netflix was glitching out, and then I used this fancy switch and now it's fine" or "My alarm clock kept losing time but now it's good with the fancy power conditioner?"
Somehow the only appliances in their houses that are affected are audio gear... hm... you mean to tell me every piece of electronics on the planet has better shielding, error correction, and power conditioning than audio gear? How odd that you also accept ad dollars from the same industry! What could possibly be going on here...?
I think the reviewers really do give themselves placebo effects with the gear. They aren't lying, or at least they are lying to everyone including themselves. But this is why you will never see any measure of efficacy for this stuff outside of audio, because you can't placebo-effect yourself into believing these things actually work except in some magical way that nobody should look into.