Vanguard says it's more of a speculation than an investment. Vanguard isn't saying speculation is bad entirely.
Stocks are ownership of a tiny part of a company that has assets, cash flow, and does something in the world. Stocks are a speculation as well, some more than others, but the balance of speculation to investment is weighted differently.
Bitcoin on the other hand is almost always only purchased for speculation that the exchange rate will go in your favor. You don't own a tiny part of anything.
From my perspective, a big issue with Bitcoin speculation is that it's inherently zero-sum. Investing in a company is usually positive-sum (even if it you don't profit).
Stocks are ownership of a tiny part of a company that has assets, cash flow, and does something in the world. Stocks are a speculation as well, some more than others, but the balance of speculation to investment is weighted differently.
Bitcoin on the other hand is almost always only purchased for speculation that the exchange rate will go in your favor. You don't own a tiny part of anything.
From my perspective, a big issue with Bitcoin speculation is that it's inherently zero-sum. Investing in a company is usually positive-sum (even if it you don't profit).