Many buy a Logitech Harmony for this reason.
I have a 2017 LG OLED TV. I often stream music to it and don't need the display on. There's a way to turn it off, but it's really deep in the menus. (I don't have it in front of me, but I think it's buried in "All Settings - Energy Saver" then click a few options and select "Screen Off" or something.)
Does anyone know if theres a quick way to do this?