Those products are to be used at your own risk. They are not FDA approved. Fssai mark is a quality check. Long term use of it is not advised for individuals who do not spend 24 hours at gym.
Gym trainers use and advise it as they are indulged all the day in Gym activities. Where as if you are an employee who works in a corporate office or any other, which has a desk office job, then it is not recommended.
How long one can depend on these powders for muscle mass.
As it all depends on how you consume diet regularly. You are wat you eat today.
I advise you to go for natural therapy that is natural foods.
Include daily 3-4 egg whites, 2-3 cups of fruits and vegetables, 2 glasses of skim milk,
2-3 cups of rajma, chole, or other pulses and legumes, 2cups of curd or yoghurt, 1 fist of boiled peanuts or soaked almonds or jus walnuts, Include regularly paneer, tofu, skinless chicken, wheat, fish etc in your diet.
With exercise and the above healthy diet you will see results.
For an individualized diet plan you can consult if its required.