Why can't my team function without me holding it all together?

You call it flexibility. It is absence of structure. Every day you are the one who must remember, decide, and explain — again — what was already decided last week. This is not devotion to your work. It is a failure to finish the work of organizing it. A system is not a binder nobody reads. It is a decision made once, written down, so it does not have to be made again from memory under pressure. You have been too busy running the practice to build the thing that runs it for you. Understandable. Still a choice, and one you can unmake. You do not need a perfect structure. You need one written process, used once, this week. Everything else follows from that, slowly, the way a habit follows from a single repeated act.