I think that the value of being "rich" is derived from being able to use that money to get other people to do things you can't or don't want to do yourself. This requires a functioning society, infrastructure, and a healthy low & middle class where those people can still afford a decent living to be able and motivated to work, provide services to the rich and consume what the rich' businesses sell (which in turns helps you be rich and remain so).
This is where I see the UK failing more and more - critical infrastructure is falling apart as people outright "check out" from the grind or leave the country for greener pastures - why would you bother working for the "rich" if you'll end up no better off? Thus service quality decreases, "nobody wants to work anymore", every business is short-staffed and failing since patronage is falling due to lack of disposable income. When this starts affecting critical infrastructure such as transportation, healthcare or law enforcement, it becomes a death spiral that's really hard to reverse.
Being "rich" in such a country is an increasingly precarious situation, especially when so much of that "richness" is inherited wealth owned by a generation that is itself aging rapidly and in dire need of good healthcare.