Is it your perception that a majority of combats in PF2 do not end when HP thresholds are achieved (zero or higher if those trigger surrender or retreat events) but they end by foes defeated while still possessing significant HP?
Every D&D version and variant I've ever played has come down to the same basic HP war in the vast majority of cases. Occasionally there will be a spell involved that acts as a shortcut.
I get that no one game can work for everyone. An optional set of rules for tactical combat could be grafted on top of combat without hurting much. But that is just a different way of implementing HP attrition.
It's up to the DM to set up encounters with a variety of goals if that's what the group needs.