Not always. That depends on whether the route is an open reimbursement model, a travel-style emergency route, or a healthcare route that relies on approved providers and centres.
This is where expectations matter. In some situations, the answer is broad access with later review. In others, the answer is approved network first. Using the wrong assumption can lead to unnecessary cost or confusion.
The safest answer is simple: choose freely only when the route clearly allows it. Otherwise, confirm before booking.