With a fourth or fifth generation Apple TV and tvOS 11, you can create folders in which you can collect similar apps. To create a folder:
- Navigate to one app that you want in the folder.
- Press down and hold the Siri Remote or Apple Remote to select the app. It will jiggle when selected.
- Drag your finger lightly on the trackpad to move the app and hover over a second app that you wish to place in the same folder. A new folder will automatically appear.
- Press the trackpad on the Siri or Apple remote to drop it into the newly created folder.
- Press the Home button on the Siri Remote to go back to the Home screen in tvOS.
(This how-to is based on my experiences and info on Apple's support pages — where the images sometimes come from.)