In places such as Iceland, where bankers have not 'integrated' so deeply with the government, the banks were allowed to crash and top executives served years in prison. [1] This included people all the way up to chairmen. It had a catastrophic short term impact, but Iceland's economy rapidly recovered and remains healthy to this day. Incidentally their current president has an approval rating upwards of 90%.

Obama in 2009 was optically in conflict with bankers. Quoting things such as "I did not run for office to be helping out a bunch of fat cat bankers on Wall Street" [2]. 8 years later, he's getting paid $400k for 30 minute talks by them, repeatedly. For some reason banks and investors don't seem so anxious to turn Icelandic presidents into multimillionaires for a few hours of talking once they leave office.

[1] - https://www.independent.co.uk/news/world/europe/iceland-to-s...

[2] - https://www.reuters.com/article/us-financial-regulation-obam...