I agree with some of your points, OP, but not with your pessimism.
The prediction of the OP was still very good so far that the model would make bitcoin fail as a currency because of the high investibility that would encourage people to hoard it and benefit from it as a pseudo pyramid scheme than using it as a currency.
The primary reason people originally hoarded Bitcoin is because of the estimated worldwide adoption as an international currency; if you got BTCs for a low price as an early adopter, you could be always sure to make a huge profit if this happened. This has changed a bit since then, now there is a significant part of Bitcoin investors who simply speculate on "catching the best moment" to buy and sell.
At the same time, there are some indicators that seem to show that Bitcoin is now even less used as a currency than, let's say, in 2015-2017. For example, in some countries there are less merchants accepting it, and there were also events like the failure of OpenBazaar's dev team OB1.
I also agree that this tendency, if it should continue, is bearish for Bitcoin, because of the reasons already explained by you and various people here, particularly odolvlobo
here. As an asset which generates no cashflows, and with an "intrinsic value" very difficult to grasp, the best fundamental indicator we have is the Quantity Theory of Money; i.e. adoption in terms of the number of transactions. So if this indicator is not clearly rising and thus indicating an adoption "as a currency", Bitcoin will continue to be a speculative "collectible" with pretty clueless investors guiding themselves primarily by superficial technical analysis (and such "fundamentals" like Elon Musk's tweets), and there is always the danger that at some moment nobody wants to be the
greater fool.
But still, nothing is lost - at the contrary there are reasons to be optimistic.
One of the biggest indicators that the "currency" usage could come back eventually is the adoption of the Lightning Network. It grew very steeply in 2021, now it grows slower but still steadily and much more pronounced than before 2021.
Lightning adoption is bullish for two reasons. First because the main use case is trading goods and services, and not hoarding (for hoarding, on-chain txs are better/safer), and second, because value is frozen in LN channels. These Bitcoins can of course be unfrozen but they will probably stay there longer than in a "normal" UTXO and thus unavailable to "hoard and sell" speculation.
Then there is the movement of states adopting it as legal tender, with El Salvador, which also should boost "currency" usage.
There is also no reason to "not" spend Bitcoins if you think it will go up more. Simply spend it and re-buy, you will be strengthening its ecosystem and network effect.
The best case scenario would be that Lightning/currency usage would continue to rise and eventually (most likely in a couple of years, not in 2022) become the main use case for Bitcoin again. Speculation will always exist, but if currency usage increases, this should result in a more stable price, even more so if eventually "fixed prices in Bitcoin" become a thing so you can anchor the value of a BTC to certain goods or services.
So a virtuous cycle could evolve: Bitcoin becomes more stable but still attractive as an investment, and as it stabilizes, it becomes also gradually more usable as a currency.