Hints why I interpret it as open ending and that he only passed out :

1) everyone else was shown fatally wounded (stabbed, shot, exploded) except for CX, the bombs also missed him. If they wanna give absolute death, they would have shown him shot multiple times and bleed out.

2) Xiao Beichen shown as alive after being presumed dead in his own drama series (If that is not hope, I don't know what is). Means also Yu army are not on their own.

3) QiXuan is there working as a nurse, it's not random.

4) one year passed and PJ still hasn't received news to confirm his death. PJ works with the communist group, surely they have more info what happens in the field. No confirmation of death, otherwise, why would she lie to her son that Dad will come back. They are clinging to a real hope that he is still alive.

I do not hope for a very clear HE as I think censorship won't allow it. Warlord era must die together with the warlords to give rise to New China and CCP. But I think this is Director's way of somehow giving a bit spark of hope.