To a degree that's pretty much true for every "aficionado" fad out there. After a certain price point, almost everything is indistinguishable. Just manufactured scarcity / "premium". I have friends passionate about wines, whiskey, coffee, audio, water??, and so on. Yes, there is a price point for every one where the difference is obvious, but after that, no one can tell the difference. We actually did a blind coffee tasting in our friend group, and most people preferred some new beans bought from starbucks out of every kind of "unique, pristine, virgin hills" stuff that's overpriced and overhyped. It's doubly funny because all my friends say starbucks coffee sucks. Well, well, well...

Snake oil in what sense? If the difference is noticeable, and some people care about those differences, I think they should be able to enjoy it. There is a lot of hocus pocus for sure, but it would appear to me that just because you personally don't value the differences offered by Hi-Res doesn't make it "snake oil"...?

I think the formats are all supported natively, so I assumed that they are played using native macOS decoders etc., not something in Chrome.

Fun fact: I started using HQPlayer, which does upsampling so that whichever DAC you use it doesn't have to, with its limit power compared to for example the M1. It really makes a surprisingly big difference!

As I noted here https://news.ycombinator.com/item?id=45396104, do you also feel like when you're listening to hi-res music with your usual setup songs sound way better than either of the samples from the web test?