"...meeting the needs of both students and research workers..."
The text is dense, terse, and requires effort of the reader. I neither agree nor disagree with the idea that it can meet the needs of students, because the concept of a student's "needs" must be unpacked. What are those "needs"? By what criteria do we distinguish between what we might properly call a "need" and what might be better framed as a student's mere "desire" or "wish"? Which wishes are reasonable for a textbook author to comply with? And who are the students that we have in mind?
While I offer no firm conclusion on whether this textbook meets the needs of students as I might wish to frame the concept, I can say with great confidence that most of my colleagues would denounce this book as inappropriate for the needs of the modern student. And so we see how the world has changed.
The Sacred Scrolls are not inerrant. While some of the the textbooks of the past are similar to the present, it's clear that Planck's idea of appropriate pedagogy is not a good match to the modern understanding. But don't worry: While we might not uphold Planck's intellectual standards, we do allow trash TV stars to become President, and we do everything in our power to make college degrees more attainable.