His greatest skill has been taking credit. He finally ran out of the accomplishments of others.
He had little to do with Tesla, aside from naming the models so they would spell S3XY and using shitty off-the-shelf components not designed for use in cars that are now failing in many vehicles. He literally bought the title of "founder" from the people that actually founded Tesla, Martin Eberhard and Marc Tarpenning.
SpaceX is the work of Tom Mueller (former TRW engineer), Gwynne Shotwell (former The Aerospace Corporation engineer), and Chris Thompson far more than Elon Musk.
Go back further, and you find his family owned an emerald mine. Paypal was far and away more the work of Peter Thiel, who merged his business with Musk's online financial services company X.com (if you wonder where that came from). He got super rich selling out to eBay. His one business, Zip2, was just good luck selling it out also during the Dot Com bubble (I mean, seriously, it was bought for $305m by Compaq to help AltaVista). Essentially, the emerald mine funded Zip2, which he sold in 1999 to fund X.com, which became Paypal, which he sold in 2002. Since then, the millions he got from that sale funded SpaceX and Tesla.
And to be frank, he wants more power, and he saw how quickly Trump was able to manipulate people. So he dropped the mask and adopted Trump's modus operandi.