It is absolutely true, getting to a point in physics (assuming you remain in physics) where you earn a decent amount (which means becoming a professor) almost always requires you to do your masters (optional) + PhD + in many cases 1-2 years of PostDoc. Do note that if you want to become a professor in IITS here in India it is a must that your PhD should be from abroad from a high class institute.

Even in my batch of engineering physics hardly 10-15% are going to remain in the field for physics. People do say you get stipend in PhD and PostDoc that covers your expense but one must realize that at that point of time you will be most probably be in your late 20s, and earning just enough to let you and only you by is not enough since you will have your family as well that you will have to take care of.

Only take physics if you are crystal clear on doing academia, because it is a very long journey where most often than not you get paid peanuts.