If this rocks Twitter to its foundation as a trustworthy platform, it's the end of Twitter as far as prominent figures being willing to utilize it. If Twitter loses its prominent figures edge, it's all coming down. Twitter has nothing else, it's mostly a broadcast platform for elite people in terms of where the extreme majority of all of its value is produced.

That said, that outcome is far-fetched. The content that was Tweeted appears to be far too benign to accomplish that outcome. The attackers seem to have intentionally avoided Tweeting anything particularly dangerous. If they were trying to ruin Twitter, they would have used the accounts to do something far worse, that would terrify prominent figures away from using the service.

I think they had one target in mind, to go after their DMs, and hit lots of accounts as a cover to hide which one was the primary target.