Most Java developers today can explain encapsulation. They will tell you it means making fields private and adding getters and setters. They can recite SOLID principles on demand. They know the vocabulary. What most of them have never experienced is what genuine object-oriented design actually feels like in practice — and that is the real problem. Object-oriented principles did not disappear because of technology hype or the pace of change. They were never properly learned. A generation of developers was trained on frameworks, not on design. They learned Spring before they understood objects. They learned dependency injection before they understood responsibility. They learned how to make things work before they understood how to structure things well. The result is an industry where object-oriented vocabulary is used to justify procedural habits.…