If you install updates or use a newer Windows release, the answer is you can't go back.
While some Explorer features may configured by using feature controls (search online for ViveTool), newer UI designs will eventually be made permanent by installed updates. You can also decide to block updates, and freeze Windows to a specific build.
Most users look to 3rd-party apps like StartAllBack, Explorer Patcher and others to get around this problem. What they do is hack the running processes and replace the UI layout with another design.
