Another analogon I often find myself reminded of is the Flying Spaghetti Monster and its devoted disciples, the Pastafarians.
I joke, but the thing is, we're indeed dealing with "believers" and "non-believers" here, and you will never be able to sort this out. It's an age-old debate, and one that will continue well beyond our lifetimes, never to get settled. And you're right, the burden of proof
should lie with the believer, but a believer can't prove what he believes in, because then it wouldn't be a belief, would it? But good luck in persuading him that what he believes in it false. And who are we to say it is? Like you, I do hear differences between transducers, but hardly, if any, differences between DAPs, DACs or amps, not to speak of cables or firmwares. Others do. The thing is,
we will never be able to decide either way. Are we deaf, or are they delusional?
We'll never know! This used to drive me mad when I still gave a rat's ass, mostly because it's so infuriating to me to see people apparently swindled out of their hard-earned cash, but I've learned to let go. And hey, if it subjectively makes them happy, it is sort of a victimless crime, isn't it? Placebo is at least as mighty as the Flying Spaghetti Monster!
And you're right that this forum is mostly populated by believers (or perhaps we should call them positivists), but there are other forums out there which are directed more at sceptics like ourselves. I try to keep my mind open as much as I can, collect as many data points as possible and form my own idea about what's what based on that. It's all any of us can do really ...
One thing I do find curious, however, is that
every expensive aftermarket cable that is bought,
every capacitor or internal wire that is swapped in for a predecessor that cost a fraction of it, unfailingly makes a "night and day" difference and
always, always sounds better to whoever forked out for it. Food for thought ...