He is still great because he's Elon Musk, that's the undeniable reality and truth, regardless of whether and/or how much he received from the "establishment". And as a matter of fact, it's only after he's proved himself that the "establishment" decided to invest in him and it's mainly for their own benefit. He single-handedly invented the massive production system of the electric car and built the company entirely with his own money and money from financial lending institutions, not really from the "establishment". He put in everything he got into SpaceX to finance the FOUR spaceship launches before the "establishment" finally recognized him and decided to partner with him. And for everything that the "establishment" has given him, he's paid more than 10 fold back. He single-handedly brought space missions back. NASA was on the brink of canceling its space program before he stepped in and revived it.
Of course this is not to excuse him for what he's done IF he's really done what he's accused of. But his accomplishment shouldn't be diminished.