Elon Musk was forcibly removed as Tesla's chairman. That was the real punishment. Furthermore, Elon Musk agreed that two new board members would be selected by the SEC. Finally, Tesla promised that they'd watch Elon Musk's twitter account better.
The $20 Million was a slap on the wrist. The "real" punishment from the SEC were those new restrictions, which should clamp down on Musk's behavior.
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No one wants to see Tesla or Elon go bankrupt. The SEC just wants Elon to be more factual in his tweets. Neither jail nor fines help anybody.
IMO, the SEC should have threatened Elon Musk's CEO position a bit more (I mean... they could push him out of any officer position in publicly traded companies), but there's a strong argument that Tesla wouldn't survive if Elon were forced out.