"There are a few advantages to owning a Rolex that may not be so obvious: For starters, it's quickly exchangeable for a high percentage of its value in cash in virtually any major city in the world."
Please define "high". I have seen a Rolex sold for less than its value in gold (gold rolex).
They have sales tax (20% in Europe). The shop has likely something like a 100% mark up on a watch. Most of the costs of the Rolex are for advertisement. You can get a same quality watch for a tiny fraction of the price.
"Because you're always wearing it, that's $8,000+ in cash that you can have in short order if you needed it badly" If it is not made out of gold, I suspect you would get 1 or 2 grand for it. On a good day.