Let me avoid the technical aspects to make things easy for all readers.
So someone said that America's NSA has this great computer(quantum computer) that could easily hack Bitcoin private keys. I really doubt his claim but I know for sure that certain computers like the most powerful Super Computers are within the reach of some of this Intelligence organizations.
Do you think such computers can crack any security codes put in place to make Bitcoin very secure?
The thing is, on paper, everything is hack-able. But when talking about hacking(or brute forcing in this situation) bitcoin private keys, I think it will take a very VERY long time for them to be able to score a private key. Were talking about long enough for multiple generations of people to die and be born.