I think that a well thought out design can make a (little) difference by keeping things as clean as possible. Same for using a good power supply instead of the noisy cheap switching types.
That is a part of what makes the difference between audio and better audio.

As for switches, I like to believe that they are commonly not build with that separation from noise in mind as its not important for PC use. A better separation from noise sources seams reasonable to me and the technical implementation isn't rocket science nor expensive. Although the prices of audiophile switches seem to suggest otherwise.

As for the measurements? I don't know, but I see a lot of serious demo's of power-conditioners and power cords with "power sniffers" which measure some radio frequencies in a non excising unit of measurement and some good ones where equalled in sniffer measurement by a 10 dollar EMC filter from AliExpress.
I own a decent power conditioner and it didn't do anything noticeable on my previous high end setup. But it does a good job with the 818 but limits the performance of the DSP7200's...

The "ill give it a try" way for me is to buy things for a price that I can also easily resell it for which makes the experience more neutral for me.

I'm not free of assumptions. From what I've read in the 90's and found reasonable was that computers in general and powered by a switching PSU generate a lot of noise and weren't suitable for good audio production. Until I came across a dirt cheap MC200 and it thought me differently after trying it.

Some Meridian...