I am studying for some Cisco Security certifications because my job needs it and I have seen there that they are talking already or at least being prepared for what they call post quantum computers encryption and algorithms type. This mean that this Sha-256 most likely can be cracked in 10-20 years as that was the time frame in the book assumed when we will be needing these next generation encryption and algorithms. I don't know why it was made public but for the moment it is one of the very strong encryption algorithms as in VPN-Virtual Private Networks site to site connections we are using it as one of the best encryption algorithm, the SHA-256.

You can read more here if you are interested in algorithms security.

https://www.cisco.com/c/en/us/about/trust-center/post-quantum-cryptography.html