1. Install a new launcher from play store (I found one called "Basic Launcher" that matches the aesthetics of the default one). This doesn't solve the problem though, because Google disabled changing the default launcher for some user hostile reason, until you delete the existing launcher.
2. Enable development mode by tapping on the build number in settings
3. Connect an adb shell to your device
4. Remove the built in launcher
5. Reboot, select basic launcher when prompted
I own a few android TV devices, have recommended them to people in the past, and won't be purchasing another. I think what happened here should be illegal and shame on whoever worked on this.