Who NEEDS Bitcoin? Sure, lots of people have got in on the speculation, which is really an argument against using it as a currency (can you imagine using a deflationary asset as a countries coin?), but why is there a need? What common use case does Bitcoin make better for the everyday person?
It's not "cast as", it just is rapidly appreciating asset.
But yeah, knowing that $100 in bitcoin today might be worth $150 in a year does deter buying non-essential stuff. Why is that a bad thing?
Personally, It won't discourage me from buying a hamburger when I'm hungry, but maybe it would make me hold on to my iPhone for a year or 2 longer but you can do as you please and spend every cent you make.
Only until the dollar hits 0 in comparison. Then, it doesn't matter what a bitcoin is "worth", since it's all arbitrary at that point and it can be used as a pure economic unit devoid of any other context.
You should really read The Wealth of Nations before you talk about currencies needing "backed" or "intrinsic" value. It's not in the definition of money at all.
Today the most common use is is as a store of value.
If you have excess cash, be it $100 or $1 million and keep it in dollars, you'll loose ~8% a year, which is the historical yearly rate of US money printing which is the real inflation (not the fake 2%; check the inflation of health care plans, college education or housing).
To preserve that value you can do simple / safe (bank savings account rate, bonds, S&P 500 etc.) and underperform that 8%.
If you want to match / outperform that 8% (i.e. not loose money over time) you have to become a successful (better than average) stock investor or invest in real estate with all the hassles it involves (like managing tenants).
Or you can invest in Bitcoin, which, historically, over 4 years, outperforms dollars, gold, us stocks.
Bitcoin outperforms dollars because US can (and does) print as many dollars as it wants, whenever it wants. Bitcoin has a fixed limit of 21 million bitcoins. You can't print more bitcoin than that therefore you can't devalue bitcoin.
It's even worse in countries like Niger or Argentina because they print even more money than US, causing even greater inflation, making it ever more important to park assets in non-inflationary asset.
If you self custody bitcoin, you remove the risk your money will get confiscated by the government or bank.
In some countries you can already pay directly in Bitcoin.
In US you can use Strike to basically store you net worth in Bitcoin and convert to cash (dollars) to pay for stuff.
