I think there's a specific "corporate style" of speaking that's very stiff and blandly positive, which is what they're thinking of when they're saying corporate speak. But I agree with your point and was making it, even though Musk speak is a different style, it ultimately works the same way as the corporate style, which is to buff up his brand in a way that maximizes shareholder value. Musk speak might not be the corporate style, but it's still a form of corporate speak, as per your definition.
Corporate speak, definition:
- to say what's in the best interest of the corporation, no matter what the circumstance
- to not tell the truth, unless it's something that can become a huge PR success for the corporation
- to not tell a lie, unless it's something that can become a huge PR success for the corporation
For the "Musk speak" definition, simply replace "the corporation" with "Musk".