How to fix frame drops in Manor Lords with population over 500?

I was so excited to finally fix the lag! Previously, whenever my town hit 500 people, the frame rate would tank during layout planning. I first tried enabling High Performance mode in Windows, which just raised my CPU temp by 8 degrees without fixing the memory frequency, making me anxious. I used the GamePP BIOS Load-Line Voltage Adjustment Wizard to lock the frequency at 3200MHz and set voltage to 1.35V. RTSS showed frame times dropped from 25-40ms to 16-20ms, and HWMonitor confirmed temps at 46-52℃.