Knowing how to run a software company and knowing how to build software are two things. The first thing usually implies hiring the right people for the second thing. I’m sure Musk knows at least a bit of that, but everything we see with Twitter is that he’s axing those people at a rate that you can’t keep up hiring at. So there is some obvious disconnect here and I don’t think “Ah, he knows what he is doing “ is a sufficient explanation.
The Zip2 application ran on a single PC. Technology has changed a lot from the early Java days(I think what Zip2 was written in). Perhaps this helps explain some of his public mistakes in understanding the codebase of Twitter.