Sure, keeping ~3 years income outside of the market if your actually retired is a good idea idea. But, just because the market tanked does not mean you lost money. You have the same share of the same companies if the market goes up or down.
If you need the money in five years, you should not be putting it in the stock market. If the money is truly "put to retirement" then you don't need it in five years, and you're just agreeing with me, pedantically.
The problem is that most of these HODL folks have never lived through a downturn, and will be crapping their pants when they realize that they really were secretly counting on the money being there. I've seen it happen twice now. The forums are filled with people "buying the dips" on 1% drops, but suddenly seeing a 30% short-term correction in their portfolio causes mass hysteria. The smart players have cash on hand, and are ready to buy -- precisely because they didn't "buy the dips".
Warren Buffet has $116 billion in cash on hand.
https://www.fool.com/investing/2018/03/04/warren-buffetts-11...
But sure, by your logic, he's "timing the market."
This is investing 101. Any financial planner will tell you the same thing. Most will tell you that you shouldn't have money in the stock market if you're going to need it within the next five years. Ten years is a better number.