Since it was fired in low earth orbit, it is not hard to understand how they did it at all. Orbital velocity is 17600 miles per hour and that is Mach 22.5.
All satellites in orbit are hyper-sonic. Try to go that fast in the atmosphere and you get burnt to vapor. The X-15 was the first manned aircraft to go hyper-sonic and that was back in the 60s.
This is all hype to make China look like an adequate enemy for the next war.
I posted in the other thread but will post here too.
They are just getting warmed up. They are certainly making some impressive technology advances in certain areas. They will need to fine tune their accuracy a bit to take out our carriers, which is where this is going.