I guess I'll be in the minority for the whole "alicorn" thing. I grew up with the actual meaning of the word. Never liked how it's misused here or in the general fandom.
Eh. The meaning of words change over time. And if it helps you feel better, it could be so named because it's an amulet made
of alicorn and not because it's an amulet depicting
an alicorn. That's a totally feasible explanation...that will undoubtedly be busted by the show referring to Celestia and Luna as alicorns somewhere down the line.