Bitcoin is a digital currency but most still prefer to see it as an asset (this is what was stated on the Whitepaper).
Aside from this, the strength of every cryptocurrency is in the blockchain (how secured and fast depends on the blockchain) and this is the means a cryptocurrency can be hacked. Hacking of wallet is not considered as an hack to a cryptocurrency itself but to the victim.
Bitcoin won't be the only cryptocurrency the world can trust, there will still be few altcoins also but bitcoin will always be the most trusted as time past.