While quantum computing might not be a threat to bitcoin directly, yet it is a threat to the security of funds when you reuse addresses. This is because when you use an address, your public key is exposes and with quantum computing, it can be possible to compute your private keys from your exposed public key.

It is better you don't reuse addresses, You can mitigate this risk by moving your funds to a new unused address each time you use an address so that your coins are safe in the new unused address.