I mean even if both Tesla and SpaceX close tomorrow, he already achieved more in both companies than most of the current "unicorns".

He successfully made popular mass market electric vehicle, and dragged whole auto moto industry behind. There were other electric cars before tesla. But tesla made it cool, and made the rest of the industry trying hard to catch up.

SpaceX also is not the first private space firm, with their own rocket, But it's by far the most successful one, and lowered the cost of entry to space by significant amount.

Also It's probably the first private space company that has rockets that can compete with most government ones.

I am not rich enough to be buying individual stocks, so I have no personal stake in this.

Well yes, but he's the cheapest provider of self-propelling pyres, and the only provider of pyres that can be used multiple times.