Do you mean anti-air as in shooting down attacking aircraft ?
As I understand it the small range (<10km) and ceiling (<5km) of the HQ-10 would mean that an attacking aircraft could use stand off weapons (laser guided bombs?) to stay out of reach.
The 056 could only try to shoot down the "arrows" not the "archer" and would need support to chase away the attacking aircraft.
Exactly. The HHQ-10 cannot attack anything except missiles and bombs. 8 of them are perfectly capable of defending against the minor, one-time attacks from a non-state actor or from one or two ships, fighters, or subs. Asking any more of this platform is unreasonable. They could have increased the armament of this ship very easily with 8 ASCMs/ASW missiles and 18 HHQ-10s without breaking its back (and they still could in the future), but this thing is a patrol vessel, not a true ship of the line. It's meant to be produced cheaply in large numbers and to deal with minor threats. Expecting this ship to survive a concerted attack or multiple attacks is just surreal.