Disable auto updates on google play store (user icon -> settings -> auto update)
Go to settings -> apps and reset "Android TV Home" to factory settings.
Get the apk of android tv home 2.3.1 (last version without ads, 3.0.10 is with ads) and install it as an update
Edit: there seems to have been some confusion: You DO NOT RESET YOUR ANDROID TV. The only thing you reset is the APP "Android TV Home" This guide works for devices that already have ads
Perfect. Update didn't bother me but the constant customize home screen bubble did