Discord did not answer questions about whether these users were repeat copyright infringers, had received any previous warnings, or were forwarded any takedown requests.
Yeah look, this isn't how DMCA takedowns work. Why would anyone think you get a practice round when it comes to copyright infringement?
And it doesn't matter for Discord if it was valid DMCA or not; Discord isn't going to take up your cause with their legal team. Why would anyone think they would? That's the job of the entity that was acted on.
(And let's set aside that there's a good chance it probably was valid for the reasons they briefly alluded to in the article. It just takes one person doing something dumb.)
Blaming Discord is silly. Any corporation would do the same. Don't depend on a corporation providing a service for free if you don't want to be subject to their judgment. There's a reason we're all on Lemmy.