Nobody's condescending here (except you, perhaps). I don't know much about audio formats myself, I clicked because I got curious of "every audio format", but got a pretty basic set of the most popular formats instead that's missing some formats that even a dummy like me knows that exist, so I'm genuinely curious why would someone add a completely unnecessary and confusing word "every" into that sentence instead of, say, "various". All it achieves is that it turns a useful submission into a lie.
But no-one is shipping content with these long gone formats any more. My almost 20 year old receiver supports formats that have long since fallen by the wayside as well, why put any effort into them for test and diagnostics?
Old content still exists. Also, there are still SACD releases being made in 2023 (though whether it makes sense is another matter) and DSD is nowhere to be seen in this set of files either.
That said, it's obviously impossible to include every audio format out there, so I don't expect it to do so at all. That's why I asked what's the motivation to write such thing, because it's a very weird thing to say in the first place. If it actually included some weird, exotic and outdated formats it could perhaps be excused, but apparently it doesn't even try to do that, so it really feels like clickbait.
The LPCM5.1 is an M2TS file at @498MB while the LPCM7.1 is saved as WAV at only 23.2MB. That seems very strange unless the 7.1 is significantly shorter. That would be very odd decision. Seems to me that a library like this would be exactly the same audio source just saved as the different formats. Maybe I'm over thinking it, and just too OCD about making a library like this public for fear of this very type of criticism