There is, in fact, no such thing as two
Boy this was a wild ride. From “too much detail” to “analog vs digital” to “ANALog”. Never change internet. Never change.
It’s all about the music that never changes…the rest is psychobabble and marketing lol 
But to actually answer OP’s question: it’s because I have a hard time turning off my thought processes and just-listening, so for a listening session to not just devolve into thinking about what I need to fix about the fridge or what reservations to make for the next vacation or who I need to call tomorrow etc., the music has to be as attention-grabbing as possible while also fitting my preferred genres and loudness. How do you grab attention if you can’t do it with loudness or annoyance? Hyper-detail.
Then I can have critical listening sessions where the music disconnects me from my daily thought process and keeps me disconnected the whole time, by firing enough detail at me that there’s no more attention-span left to dedicate to anything non-musical around. In fact I would say that any high-quality recordings and gear that aren’t periodically used in this way are being wasted/disrespected. 