Concerns

Quantum computers could disrupt privacy and cybersecurity with potentially serious negative consequences if organizations are not prepared.

Quantum computing may decrypt data using encryption methods, which might lead to data theft if companies are not prepared to adapt to post-quantum cryptography. Without sufficient security, many of the alleged benefits of quantum computing may not be realized.

The signature mechanism used by Bitcoin and other cryptocurrencies will ultimately be cracked by quantum computers, which poses a serious concern since it will cause the market to collapse. The value of the coins would decline completely.

Quantum computers could be extremely dangerous and I would say even more dangerous than AI or nucleur weapons because of the amount of power it holds and how much it could do. Who's to say that a Quantum computer can't figure out nucleur launch codes?