Well it dramatically decreases the efficiency of the monetary system (requiring 60 days of electricity and 1 iPad of e-waste to scribble a few bytes into the ledger every 10 minutes), and only one of the other assets you pointed out create value, the others are unproductive.
Real estate is not a monetary asset, it's a productive asset - because people need a place to live and you can either live in a house yourself or you can rent it to others. This demand doesn't go away through the introduction of Bitcoin.
Gold is a commodity, not a monetary asset. While a large amount of its value is attributable to speculation it has myriad industrial uses, and jewelry use. Some of this demand may go away as there's a large overlap between goldbuggery and bitcoin maxis.
Dollars have no intrinsic value, but instead their value is derived from demand which is created for them when they enter circulation. They're created via fractional reserve lending meaning that when a loan is issued, new dollars are created but also a debt is recorded - creating demand for those same dollars. That means dollars are 100% backed by demand for those dollars. This demand doesn't go away through the introduction of Bitcoin.
Bitcoin is nothing. It has no intrinsic value, it has no demand, it's simply a speculative number-go-up machine. It's not money, that's for sure. You could try and use it as money but that would be an utter disaster from a macroeconomic perspective.
So yeah, parent is right, its roughly a pyramid shaped MLM with a negative-sum component - the $60,000,000 per day you have to pay to miners to keep the music playing.
[edit] Also note that gold and real estate are not classically defined as "monetary assets" - those are for instance cash, bank deposits, investments in debt capital markets and lease investments. Monetary assets need to have a prescribed value in exact dollar terms.