Impossible to defend realistically because if they're able to fire off volleys of them, they won't be detectable by targeted ships until well inside the range of HHQ-16. And while they may be fired to intercept and provided there is good enough tracking by fire control radar even 20km out, we'd mostly be relying on HQ-10 and CIWS guns in terms of active defence.
YJ-18 is also a fantastic anti-surface weapon. Frontal RCS is still low correct and it is sea-skimming which means detected at radar horizon at best and by then it's just gone supersonic and accelerating towards mach 3. This isn't about the conversation though. LRASM combined with J-35 just makes sense.
Let me first start off by saying that I think developing more stealth AShM is the right approach. That could be a whole new subsonic AShM that relies on passive sensors/advanced datelining. But they could also develop newer versions of YJ-18 that uses similar passive detection/communication and use more advanced material to reduce RCS. Either way, as radar technology continue to improve, the attacking weapons also need to become harder to detect than before.
Having said that, PLA is already probably world leading when it comes to detecting and tracking stealth flying object. And they are only going to be improving in their counter stealth technology over time. Whether they are facing a stealth supersonic AShM like YJ-18 or a really stealth + lo emission subsonic AShM like LRASM, their tracking capability will only continue to improve as more 5th gen aircraft joins service with more capable aerial ISR assets around them. All of these assets will be able to cue up air defense systems on the Type 055/052Ds so that they can engage targets much further out. That's why I'm not scared of saturation attacks by LRASMs. I think we are just in a cycle where both sides are continuously improving both the evasion and tracking technology in order to be able to penetrate the adversarial air defense first.
If we look at 10 years ago when CV-16 first joined service, I don't think its escort would've been able to stop saturation attack from USN carrier group. Maybe that would've been the case even 5 years ago. But since then, we have added Type 055, more capable ISR assets, CEC between carrier assets and ever improving command and combat system. And PLAN carrier group will keep getting better at air defense as quad backed MR SAM, 5th generation aircraft and new drones join service. As we look forward, I don't see USN able to improve its missile penetration capability more quickly than PLAN is able to improve its own missile defense capabilities. So, that's why I'm not concerned. Does that make sense?