Agreed. We follow agile, and we have a team of product owners who know where the project is likely headed in the next 3 years. Our sprint to sprint is usually pretty predictable, but we can and do make adjustments when new requirements come in. The product team decides how and when to adjust priorities, and they do a good job minimizing surprises.
It works pretty well imo, and it hinges on the product team knowing what they're doing.