I’ve watched the audiophile chats here with great interest over the last couple years and have reached the conclusion that the line between snake oil and improved performance is highly subjective. Part of my fun in the hobby is acquire knowledge and apply it to a MidFi budget. I have incredible sound per dollar thanks in large part to knowledge shared here.
My day job for 40 years has been at the steering wheel of a successful boutique ad agency that provides marketing strategy, brand positioning, creative services and placements. IMO no money is wasted if the buyer gets what they wanted, it’s all about marginal utility. I’m thrilled at my $4k system and it is entirely possible that my neighbor gets equal satisfaction out of a theoretical $40k system.
All cables are low pass filters of some sort, and in a high resolution stereo every one will probably sound a bit different at first use. How much that is worth is up to each purchaser.