Markets fluctuate, long term investors don’t worry about it too much. That said, everyone has to assess their own comfort/risk level. There is no perfect investment.
The problem with the market for retirees is that if a crash hits at the wrong time they may get hurt very badly.
Young people have the luxury of being long term investors.
The trap for them is that a market crash often happens when the economy is in tough shape which increases their likelihood of being laid off—in many cases they have no choice but to dip into their investments to survive which makes all the previous “financial analysis” worthless.