Without going through my entire argument, vinyl's not more pure nor more accurate. The things they like about the sound of vinyl are the flaws and inaccuracies...It's just not this pure & perfectly accurate thing that people think it is. And then good luck keeping whatever fidelity the records have after repeated plays...
Precisely correct, it's mathematically proven (Nyquist-Shannon Sampling) that the CD audio standard captures and reproduces all discernible frequencies that humans can hear. What you put in is exactly what you get out from a storage medium standpoint, with the standard. You're right to state that it's the character people like/enjoy from the vinyl, but it's definitely not more detailed than a CD.
Amidst the ocean of variables (original mixes focusing on audible range/frequencies, better THD ratings on older receivers, speaker designs focused on fidelity and not size, etc.) the whole arguments chalks up to "It depends" from my perspective. I have a lot of vinyl and a working turntable, receiver, and speakers from 1979...but I'll readily admit it's not putting out more detail than a CD played through my Nakamichi CD deck would on the same setup.
How CDs (and audio in general) are mixed today is a different topic entirely, but it's worth noting that it muddies the waters on this topic.