If someone said "I'm the fastest man alive! I can run at the speed of sound!" And then they went out and ran at 30% the speed of sound I think it would make sense to say "That was an amazing try. You're not at the speed of sound, or even that close to it, but you're definitely the fastest man alive and that is amazing running." I don't think it would make sense to call this person a fraud.

The problem with the logic is that he’s commercializing the over-promises. Investors are buying his stock based on those missed promises. People are buying cars based on that too and are being let down.

Underdelivery is par for literally every human institution on earth.

The federal government underdelivers. Corporations by default underdeliver. Grad students underdeliver. Football teams underdeliver.

Every single institution on earth more ambitious than lawncare services makes lofty ambitious goals and then achieve maybe 20% of them. Musk is the same, but the difference is that his 20% are orders of magnitude more ambitious than anyone else, so 20% delivery is still world-changing.

What he "under-delivers" is still a lot more than most other companies deliver, maybe every other company.