You're right, it's old news. Especially if you read the actual article.

'Robert Stack, deputy assistant secretary for international tax affairs, rebuts certain "myths".

"Fatca provisions impose no new obligations on US citizens living abroad... US taxpayers, including US citizens living abroad, are required to comply with US tax laws," he says.

"Individuals that have used offshore accounts to evade tax obligations may rightly fear that Fatca will identify their illicit activities. Yet a decision to renounce US citizenship would not relieve these individuals of prior US tax obligations."'

Why do Americans give up their citizenship? Tax evasion. In 2008, for example, one of the co-founders of Facebook (Brazilian Eduardo Saverin) gave up his American citizenship just before the company went public.

Evidently Boris Johnson (current Prime Minister) had dual citizenship, which he recently renounced, as he didn't want to file tax returns for both nations anymore.

Of course, there's also the case of Vincent Cate, an encryption expert living in Anguilla, who chose to renounce his US citizenship to avoid the possibility of violating US laws that may have prohibited US citizens from "exporting" encryption software. So, not directly about taxes, but about money nevertheless. It's all basically about money.