Trademark law is kind of about hypotheticals though. The purpose of a trademark is to prevent theoretical damages from potential confusion, neither of which you ever have to show to be real

In this case the trademark existing and belonging to Oracle is creating more confusion than no trademark existing, so deleting it is morally right. And because Oracle isn't actually enforcing it it is also legally right

Imho this is just the prelude to get better press. "We filed a petition to delete the JavaScript trademark" doesn't sound nearly as good as "We collected 100k signatures for a letter to Oracle and only got silence, now we formally petition the USPTO". It's also a great opportunity to find pro-bono legal council or someone who would help fund the petition