The GRE tests your ability to read, reason and write. The Graduate program is a lot of work and you have to read and write a lot. These skills are easy to learn but difficult to master. If you prepare well for the GRE, you’d come off with a much stronger vocabulary and reasoning ability. This is a useful asset in academia, as well as in everyday life.
The Quantitative Reasoning will be trivially easy for any STEM student. Refreshing the basic math concepts won’t take much time if you were good at high school math. Take a few practice tests to ensure that your speed and accuracy is adequate.
The Verbal Reasoning section is where most Indians need a plenty of preparation. You need to spend some time in studying vocabulary because you won’t be using words like Persnickety, Tergiversate and Insouciance in your everyday life. (unless you are Shashi Tharoor)
GRE can hurt your application but can’t help much. Good universities will not use this as a criterion, but more as a filter. People will place much more faith in your track record over several years than over your performance on one day on something much more rudimentary than collegiate material. Your academics & related achievements, Your college reputation, Your goals & plans plays a bigger part for you admission in the US universities.