We have the exact same topic as JTB. The high-level planning (sprint planning, roadmap planning) was relying on sections. We would add new ones (e.g., 2020 Q2) and close the ones in the past or when all tasks in a section are completed.
Since board/list switch has been released (a feature that is great, btw), we wonder how to re-organize our processes. That was, btw, also the reason why we never used the board view for this projects before … it was not possible to hide/close columns with task in it.