You are taking risk when you are investing in BTC; what's the wrong or arguement there? Did anyone say it's not Halal? If they do, what about stock? That certainly can't be Haram.
It is purchased for Gambling or Speculations, and used in illegal or unlawful transactions”.
Have you ever been forced by anyone to buy bitcoin and gamble with that? Well, I can use BTC to buy a tshirt; I can use fiat as well to buy a tshirt. Did it make any sense to you?