Given the state of ... well, everything ... it still surprises me when people pretend there's some level of modesty or decorum the rich and powerful still need to abide by at the risk of some sort of popular revolt. I guess it's a way to compensate for the material powerlessness most people actually experience (especially in politics), much like the handwringing over the Second Amendment in the US as if merely handing a town full of ordinary people guns is sufficient to defeat a modern military. Sure, it looks like nowadays you can do that with a stockpile of low budget drones because even the military industrial complex has found a way to optimize for profit by literally delivering nothing in return for extracting the lion's share of the federal budget, but even that still requires actual work like planning, training and organizing with sufficient political motivation, not just going to the range or "hunting".

The expectation of a need for decorum against all evidence almost seems like a quaint remnant of the aristocracy at this point. There's no advantage to being a nice or sensible person if you're a billionaire. People talk about "business" like it's still the 1800s and billionaires are the factory owners. The real economy (i.e. anything involving any pretense of being an exchange of goods and services in any shape or form) is now a minute fraction of the global economy. Everything else is finance. And if the nature of the finance "industry" wasn't obvious enough the US has given up all pretense to the point that members of the US government now intentionally manipulate online betting "markets" directly.

You may have needed some table manners to be able to run a tincan factory. You can let your entire ass hang out on TV 24/7 and still be a billionaire today. And people will still cheer you on like you're the inventor of sliced bread.

I guess you don't observe those billionaires yourself. Is it possible the cartoonish image you assume to be obvious comes through media channels and your societal bubble layers?

This “billionaires couldn’t spend their money” thing comes up a lot, and it show’s a child’s idea of what people might spend money on. “$1000 a month buys more ice cream than I can eat and more toy cars than anyone can play with, and I don’t want anything other than ice cream and toy cars, so nobody needs more than $1000 a month.”

I can think of loads of things I’d do with hundreds of millions of dollars of disposable income. Make large buildings that look like how I think buildings should look, fund scientific research in areas I’m personally interested in but have little aptitude for, find artists that align with my tastes and give them the ability to realise their visions, contribute to political organisations and charities that align with my values, et cetera. Those all are basically infinite money sinks.

In the past, the ultra-wealthy did do all of these things, funding loss-making research and expeditions, monumental architecture, philanthropic organisation and artistic works. The problem might be that you think billionaires shouldn’t do some or all of these things, but that is a very different position than that they can’t do any of these things.