That’s interesting! The simulation happens in a background thread (or threads), so the GUI and camera should always be smooth, that’s working as designed. If you’ve built the project via CMake with Release build type (CMAKE_BUILD_TYPE=Release), the build options (e.g. optimization level) should’ve remained the same. Otherwise, CMake might have selected a default non-release build type, which will be slower.
Another cause might be the compiler. I’m using MinGW 10 to compile Windows binaries, and using a different compiler (e.g. Visual studio) might explain the slowdown.