> A simpler theory might go like this: Musk and Zuck both want to be richer, and both want a government that regulates, investigates, and fines them less.

I agree with your conclusion, but not your premise. If they solely wanted to be richer, the obvious move would be to divest their holdings and start their own broadly diversified wealth funds - similar to Warren Buffet's Berkshire Hathaway, Norway's Sovereign Wealth Fund or Saudi PIF. Then retire to their yachts and private islands. Rather, it seems to me that they both have specific goals they want to accomplish and are making the (ethics aside) rational moves to limit government interference.