That's not aimbot. He's just playing with a low sensitivity. You can also change your mouse sensitivity either by going through your game menu > options > controllers setup > mouse settings and you should find an option to change your sensitivity or you could change your sensitivity by writing a client command : /setconfig game_sensitivity <value>
I believe Rajput has also changed his game sensitivity ratio what seems to be the y-sensitivity. This can be changed by writing the client command : /setconfig game_sensitivity_ratio <value>
And then you've some mouse(probably gaming mice) that comes with some softwares that provides features to adjust the mouse sensitivity.
I hope this clarifies. Report Denied.