A representative of hardware wallet producer Trezor explained why self-custody is a valid solution to cybersecurity concerns.

which is one of the most extraordinary properties of bitcoin. However, this also means that if you lose your private key, you have no fallback option and your funds will be lost forever.

a quantum computer with 13 million qubits would take a day to crack a private key associated with a vulnerable Bitcoin address. Google’s Willow only has 105 qubits. Indeed, Google themselves ...