This was actually a theory I had when I was posting this-
For various reasons, there is a lot of great and inspirational art when it comes to Classes and Monsters and other stuff in D&D ... but not magic items.
Heck, if I was to think of the most iconic magic item image in Fantasy, for me ... it's probably this ...
Not joking, either. There was a WHOLE GENERATION of D&D players confused when they looked at Appendix T in Unearthed Arcana.
Why is this? Why the lack of great magic item art? I'm not sure, but perhaps a 20,000 word essay might shed some light on the subject.