I believe that hypersonic missiles over long distances are slower than exo-atmospheric/ballistic missiles and have the deficiency that they produce very large heat signatures, readily detected from space by satellites - likely the same ones that currently can detect ballistic missile launches.
Sure, it's impressive to make a vehicle that can operate under those conditions, but it isn't useful to do so when existing better solutions already exist.
"Jiang said that a hypersonic aircraft could easily reach anywhere in the world within two hours." That's at least twice as long as a ballistic missile takes.