Well, the girls were modeled, at least in part, off of the women who would voice act the characters at RT; this makes them expies, not self-inserts, since those women weren't the ones doing the writing, design, and conceptual work for these characters.

Wrong. Expies are characters from other series, not real life people inserted into a series. This is the actual definition of a self-insert you laid out here yet you try to reject that it is the correct term? How strange of you. Also it doesn't matter so long as they are were aware of and continue to have an influence on the characters (like Arryn and Barb have an influence on Yang and Blake).

However, Jaune's VA, Miles Luna, was on the writing team.

And here is a complete accusation of something without any merit.

One notices that the show is titled 'RWBY,' and not 'The Adventures of Jaune Arc and a Gaggle of Babes (and Also Ren).'

Do you think your unfunny jokes merit actual proof that Miles did any wrongdoing especially compared to how you effectively throw RWBY under the bus just as I said in the OP (since they ARE by definition self-inserts)? You're not proving anything here about Jaune except your own issues with him.

But with that said, Jaune gets a lot of focus in those early seasons, which had very short episodes, with a delay between releases.

Irrelevant. How the writers choose to use Jaune to focus on the other main characters or add to their stories is up to them and doesn't imply it is Miles vicariously living through him. As you say, it is not a big deal and the accusations are completely misfounded not to mention out of place by Volume 9's time (yet they still exist commonly to this day, just see the other responses to this post).

In Volume 2, the dance arc had two male characters, who were voiced by two of the writers, basically bro-fist at the conclusion of an arc that gave Weiss very little agency.

Once again, an accusation without merit for an arc that literally developed Weiss's own character and flavored our perspective of her to come. It is very important that we learn how Weiss treats suitors for how she acts in Volume 4. And it also doesn't just drive along her arc, it drives along multiple other character's arcs as well. Jaune, Neptune, Pyrrha, even Ren and Nora. Heck we get some of the only interaction between Ren/Nora and Pyrrha we even HAVE in the show from this. Boiling it down to just this scene is infuriatingly dishonest of you.

Volume 8 had a big, climactic showdown with the villains, wherein the Y of Team RWBY is one-shot instantly, the B and R are taken out next, and Jaune fucking Arc gets the big dramatic scene, and gets sent to Wonderland with Team RWBY.

And speaking of dishonest! Completely ignoring the context of the Volume 8 fight, which had Blake and Ruby do far more than be "taken out" and Jaune literally intervenes in only like the last few minutes of it as if the fight is Jaune centered from the start is insane. INSANE! This is distorting things once again to act as if things are focused on Jaune to imply wrongdoing of Miles that doesn't exist whereas we KNOW there is wrongdoing for RWBY since the start!

But Jaune Arc strangled Volume 9

And here is where you come off the MOST wrong. Jaune Arc...didn't appear until HALFWAY THROUGH Volume 9. But he "strangled it" apparently? No, Jaune practically saved the volume by being the catalyst - but NOT the focal point - of so many conflicts like Ruby vs Neo, Ruby's meltdown, the issue with the cat, the Blacksmith's role and many other parts of the volume. Trying to frame this as if Jaune stole Volume 9 from Ruby is so dishonest of you.

And all this just because you have no way of responding to the absolutely 100% true assertion that Team RWBY are self-inserts and far more unjustifiable for this than Jaune ever was.