Fascinating discussion. I've not read every reply thoroughly, but I want to add a thought. I have made digital recordings of the best vinyl records I own. Playback of these recordings is indistinguishable from live vinyl playback (blind-tested).
The reverse is not true. I don't have an easy way to know if a particular vinyl pressing of an album was cut the same master as the CD release. However, I am confident that most listeners could easily distinguish between the two during playback.
As a practical matter, recording and mastering quality for a given album trump delivery format. If the best-preserved recording of a performance exists only on vinyl (e.g., tapes are degraded or lost), then vinyl will be the best format for that album. The same applies if all digital masters suffer from dynamic range compression because the mastering intent was earbuds listeners.
Another practical point: I have listened to a few systems that were highly optimized for vinyl playback. Every component in the analog playback chain was selected for maximum synergy to deliver an even, engaging response. For example, if the speakers were overly forward, a phono cartridge was chosen with a more relaxed presentation. The owners usually did not apply the same care when they added digital playback capability to these systems. As a result, vinyl playback genuinely sounded better, but that need not have been the case.
Ultimately, it does not matter which format is objectively superior. Vinyl will generally sound better on a system that is turned better for vinyl playback. The best available master for a particular album will generally sound best, regardless of delivery format (ignoring flawed pressings, damaged media, and low-bit-rate MP3 :-).