I bet if lawmakers said capital gains tax is bumped to 20% everyone of them would bitch and moan for 30 minutes, and then pay the damn tax.
Susan Bayh, ex senator and governor from and Indiana married to another senator, sat on multiple boards between her own political terms and while her husband was in office (also while she was governor). She's been on at least 14 boards in total: https://en.wikipedia.org/wiki/Susan_Bayh
Personally, I don't think it's the worst. I would rather they had to do this than get huge retirement packages as they do in my country after their service. Also, if their spouses can make a living being involved in business so politicians can't use sympathy for their poor family as leverage to get higher compensation that would be good too. But we can't handwave the issue of corporate influence over politicians however we choose to deal with this.
The old "you pass legislation that we want, and we'll have a seat waiting for you on the board after your term is over, with a nice paycheck attached".
Brazil
Mexico
Argentina
Venezuela
Ecuador
2 have a problem paying their bills on time. If you don't like Mexico I have some unfortunate news for you regarding Ecuador.
So that leaves Venezuela...
Regulatory capture is the biggest enemy of free markets.
Sweden has a capital gains tax of 30%, two to three times that of America and they have a similar GDP per capita, depending on the year.
That's not a law of nature, just an artifact of the current legal regime. It would definitely be a challenge to update the law to make it harder for capital to hop between jurisdictions to avoid tax, but it's also a challenge to collect individual income tax, so I think it'd be doable if the political will was there.
Historically this was not the case at all. It's only during the modern neoliberal era that this is true.
Thing to remember Capital isn't a primary resource like energy, infrastructure, materials, and labor.