This article has mixed up a few details. SHA-256 is not a form of encryption, it is a hashing algorithm. When the paper talks about quantum computers one day being able to break Bitcoin's encryption, they're referring to the 256 bit ECC (elliptic curve cryptography) public key cryptography that Bitcoin uses.
It has been well known for many years that current public key cryptography algorithms (ECC and RSA) will be vulnerable to quantum computers. And when that does happen, it'll have a much larger impact than just Bitcoin. Most secure networking relies on public key cryptography. E.g. HTTPS, which uses public key cryptography to verify the identify of the website you're connecting to (via its digital signature) and to establish a secure communication channel. All of these protocols will need to switch over to quantum resistant algorithms prior to quantum computers getting too fast, or we're all going to have a bad time.