Somewhere down the chain stocks invest in actual production value, which creates goods or services that people use, and increases the sum total of wealth in the world.
Buying the stock is buying the rights to a stream of income based on that productivity.
These "investments" in cryptocurrency don't have that aspect whatsoever. There is no claim on productive enterprise involved, and for the more niche offerings that have some element of that the economics are so wildly divorced from the fundamentals of productivity to make the link meaningless.
> There is no claim on productive enterprise involved
That's not true. Many coins offer practical solutions to real world problems. Whether they are adopted at scale is the gamble. Very similar to betting on companies with stock.
Theoretically. But it's kind of like betting on a 4 person seed stage company by raising a $3bn Series F round. Except with no actual legal ownership claim on the productive assets of the company. Which means it's actually nothing like buying regular company stock at all.