I would contend that the OP's original statement is in itself intrinsically false. They actually do indeed give the layman a general idea of "what" is being researched/studied. Naturally, they fall short in the department of "how" and "why." However, as others have noted, this was never the purpose. For example, I can know that black holes are a widely acknowledged phenomenon, but I do not need to have an intimate understanding of the math demonstrating this to still contemplate the actual possible instantiation of the theory. Much of the beauty/wonder inspired in the reader of popular science comes from the very fact that the science itself is so mysterious and foreign in nature. It's unlike anything else in their lives, and for this reason, gives a unique pleasure.
If what you purport is that a layman cannot have any fruitful knowledge regarding theoretical physics without an understanding of the math substantiating the claims, then this is similarly foolish. For I could just as easily begin to point at the most mundane of objects and demand that you need a deep understanding of the object's mechanics to understand it's purpose/qualities. For example, I am sure that most people know that a car engine has pistons that, through some vague process, causes the car to move. However, they do not need to know all of the different mechanical bits in between the pistons and wheels to grasp this concept and be able to have some level of fluency in the general qualities of cars.
To categorically reject the worth of popular science seems silly, and hurts yourself than anybody else. The layman is generallmy only tolerant of science when he comprehends some perceived benefit. Since (correct me if I'm wrong) pure theoretical physics yields few practical benefits for the average person, popular science is one of the few things justifying the support of the field in his eyes--it satisfies the philosophic impulse of the "why" in many people. How do you expect anybody to endorse your continued research if you retreat to your ivory tower and disdain those whom make your inquiries possible in the first place?