Shadows are frame killers. A true 189 FPS mod will set shadow resolution to 0 (off) or a minimal 64x64 pixels. Some competitive players consider this "cheating" because it removes dark hiding spots.
18;write_to_target_document7;default0;100b;18;write_to_target_document1a;_4ETuaarXPNCP4-EPrsKF6Qs_20;10bd; 0;16; 189 fps boost mod link
Instead of installing individual mods, many players use dedicated launchers that come pre-packaged with these "FPS boost" mods: Lunar Client Shadows are frame killers