Modern codes like opus are much more efficient. At high bitrates they are fully transparent and anybody who claims to be able to hear a difference is full of shit. Put them in a controlled setting and they fail every time.
Some Young folk think that 24bit/192kHz is the one-true-form who would think a 16/44 FLAC is a lossy encode, and then there's the vinyl folks. (I like vinyl, but not for the fidelity).
Required reading: https://xiph.org/video/vid2.shtml
Maybe I'm old, but I do not hear a difference between 128 kbps opus and flac. I mainly use flac because it is an excellent archival format and you can encode it to different formats easily.
Of course there are other ITU tests that work without hidden references, looping or even A/B comparison. They require a much bigger listener pool, are more expensive and take longer, thus used less often during development.
I'll trust actual validated limits of human perception such as 16/48 audio, 1~3dE colour, etc. And techniques used in video encoding like psnr, ssim, etc are also pretty well grounded in science. Also SINAD
But anything involving a human blindly comparing audio is into audiophile pseudoscience territory, no matter how large a cohort of people or how it is executed
No, this is nowhere near pseudoscience, psychoacoustics is an established field of science.
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