This seems like a very open-ended subjective morality question.
Must privilege come with obligations? Not of logical moral necessity in all cases, I wouldn’t think, no.
For my own moral views, thinking about the current situation, I’d say such a question really varies greatly in the specifics. All of the many actual details of the example as well as the mindset will shape the answer.
Personally, I’d say that billionaires making more billions while others are in dire need probably do have a moral obligation to do good with the power that comes from their position, at least.
And personally, I’d also say that a retired person with enough to live comfortably might also be considered wealthy, but needn’t feel obligated to put themselves out, though they might well choose to do good as well.
@SQUEEKY2 Why would you write that? I would not guess that at all. In fact, it appears to me that some of the worst problems this planet faces is the humans who both have more wealth than they have any real use for, yet are preoccupied with gaining more and more wealth, with no end in sight, leveraging the power of wealth in a futile game to increase it, at the real expense of so many others, and the likely eventual destruction of life as we know it.