The personal computer version is indeed noticeably better.
In my game, unity builds for Windows and WebGL also work differently if we are talking about the reaction to mouse movements. But my case only applies to the input range. The browser version is limited by the size of the screen where the invisible cursor moves, while the desktop build allows you to rotate the camera without restrictions.
Your game has a similar feature. But in your game, the sensitivity of the mouse is also different, which seems strange to me.