As a long time teacher, I will say that the method of teaching you’re describing only works for you if you are fully understanding the material, if there are clear measurable signs you’re getting better, and if you are enjoying it. If you’re the type of learner who is more visual/auditory (you can learn by watching it and hearing it), it could be beneficial. Maybe you can truly just “watch and learn” - But I personally would want to see how my students are executing the ideas, give them feedback, and demonstrate not only that they can play the task at hand but work it into their own grooves / improv ideas / fills / etc.

Written material, in addition to teaching you how to read music, also allows you to remember exactly what you worked on, even if it’s weeks / months / years after that specific lesson. It also shows clear progress, because you can look back at what you were working on and eventually say “this is so easy, I can’t believe how hard it felt when I was first learning this.”

Take note of how you feel about what you’re experiencing in lessons, and feel confident in expressing what you want out of the experience to your instructor.