I think both you and the article are correct. Here's a bit more context [1], it seems both Ruby and Coral were considered in part due to their connection with Perl, and in the end Ruby won because it "sounds better" and also because it's Matz's birthstone:

1: https://web.archive.org/web/20110717205734/http://blade.naga...

Edit: this also provides a clue for Perl's naming, it's "related to a shell" (I don't know if this is accurate)

Joke for Pokémon fans: Surely it should be called Platinum then?

[Explaining / Ruining the joke: Pokémon games come in paired editions - red/blue, gold/silver, sword/shield. For the fourth generation of games the paired editions are Diamond/Pearl.

In many generations an 'upper' edition is later released - Yellow, Crystal, Emerald - this is a slightly enhanced remake, often with a tweaked story. For the fourth generation the upper edition was called Platinum.]