The article mentions "designed top speed of 600 km per hour". But then a bit further it mentions "Now the prototype has achieved static levitation and is in good condition" (emphasis mine). That leaves me wondering what was the actual speed reached during testing and what will be the actual operational speed.
Don't get me wrong, I still find this project impressive.
But there's a fair amount of boasting going on as well. For example the French TGV boasted a measured record of 574 km/h. But that's on a (modified) test unit and a test track. Operational speed is about 320 km/h on most tracks.
Perhaps they simply haven't gotten to the testing/benchmark phase yet.