Buying a share of corporate stock gets you an equity interest in the companys assets. In theory the price of the stock reflects the value of this equity. And the up/down moves of the price reflect investor opinion of their future prospects.

Buying a crypto coins does not give you an equity interest in anything. However while you own such coins you will benefit from prices changes. And like corporate stock these price changes reflect investor opinions as to the future prospects of the coin and the network and contracts that support it.

Other members here may clarify this further for you.