Quantum and Relativity were lumped in "Modern Physics" in my day.
I took the course, and I could work the problems in the book and pass the exams. I even got my "Gentleman's C" in the course but I never did understand it intuitively. It never made any sense to me the way classical physics, particularly mechanics, did.
Your outline of the philosophical and historical outlines of 20th century physics is spot on. But you also correctly point out that its all just pointless navel gazing until it is actually confirmed by observation and experiment. That's what scientific amateurs and dilettante philosophers can never seem to get through their heads.