Android TV is still a new and underutilized platform. Many developers may not see a reason to support it. If you see an app that you believe would be perfect for Android TV, like user Shane_R_Monroe of the GeForce forums, it might be a good idea to suggest it to the developer. The worst thing that happens is a canned response that basically says no. However, this could be the motivation the developer needs to add it to their feature list.
X-Plore File Manager is a file browser that lets you look through your system files, with support for SMB, FTP, DLNA, and a bunch of other things. It’s a pretty capable application. The app was already built to run great on Android phones and tablets, and was a favorite for Shane_R_Monroe. As he describes in this thread, he used the software APK2TV to create a leanback version of it for himself but it wouldn’t work for everyone.
When he contacted the developer and described the modifications he made to the apk, the two worked together on refining the official app, and now it has been updated in the Google Play Store to support Android TV:
✔ Support for Android TV
✔ Read-only support for USB OTG
✔ Other various fixes and improvements
This gives the developer access to millions of potential new users downloading the app without doing much work, which is great for everyone.
Developers are often happy to add compatibility to their app for interested users, but may not know users want it without it being explicitly suggested. They’re building things for you, so many are willing to listen to suggestions.