Yes, but it's not forever... In dozens of years big computers will be able to break the encryption and find the private keys of these accounts. Maybe before 2047....
But the big question is how do you find out in this millions of bitcoin adress in which address it is locked and in which address there are lots of bitcoin.
Is there anyway?i mean say someone dies with is private key in saved in his mind without saying it to anyone.
What now?
also finding such address is tens to impossiblem