I disagree with both the premise and the conclusion.

As far as I can determine, Musk is the sole founder of only two companies -- SpaceX and The Boring Company. The former is clearly valued at >$1B; the latter is not.

He is also the cofounder, with many other cofounders, of a variety of other companies: Zip2, X.com, OpenAI, Neuralink. OpenAI is clearly valued at >$1B; Musk was one of eleven cofounders. My assumption is that your third company is X.com; Musk was one of four cofounders, and the company then merged with Confinity (also multiple cofounders), then took the name PayPal (which had been a Confinity product). PayPal is clearly worth >$1B today. I would find it misleading to say Musk "founded OpenAI and PayPal" given the above, but up to the reader.

Whether this is "more than luck" -- in particular, whether it's actually due to Musk's good leadership -- is far from proven. OpenAI, for example, had $1B in capital pledged at founding, suggesting it was already valued at over $1B at creation time. And the skill sets required to found a later-successful company versus to lead one are distinct. Musk might well be a great founder but bad leader.

(Of course, the obvious intent of my original post was to be a snarky dig at someone I view to be an atrociously terrible leader whose success has been due to a combination of others succeeding despite his influence and simply going all-in with huge amounts of capital every time. If you're not already inclined to view Musk that way, and you believe he's actually a successful businessman who is brilliant if eccentric, then a joke post on HackerNews won't change your mind.)