As of now there is no direct gain of having gate score while applying to a private firm however it will give you some edge over others because your hiring manager will be well aware that given you have a decent score in gate you know the fundamentals of the branch/area .It actually widely varies depending upon the industry you are applying .
You can consider a good gate score as something that adds value to your profile when you are being considered for a position.More important are the skills, that they will be testing you on during the recruitment process.