Why does Granblue Fantasy: Relink stutter during team battles?

I felt totally robbed of immersion during high-intensity dungeon battles; whenever the team unleashed flashy skills, the micro-tearing was unbearable. I tried enabling Windows Game Mode, but while my minimum FPS rose by a measly 2, the overall response latency stayed high. I then used the GamePP Resource Scheduler to force the game process priority from Normal to Real-time and killed redundant background services. After this, CPU temperature held at 62-68℃ per AIDA64 and frequency stayed at 4.4GHz per HWInfo, with frame time converging to 8-11ms via RTSS.