But, we can still able to buy US's company stock even we're not an American, I'm not sure in your country, but in my country I can use local broker to buy US's company stock. Although it's true Bitcoin is more widely since no one can stop people to own Bitcoin.
You can buy bitcoin no matter where you are living and your nationality. You can do it legally if Bitcoin exchange is allowed by law in your country but if it is Alegal, you can buy it too without considerable potential problems by laws and with government.
If Bitcoin exchange is prohibited (illegal) in your nation, you can still purchase it through non KYC exchanges but you surely must concern about legal issues potentially with government.
https://newhedge.io/terminal/bitcoin/legality-map