On some channels when an add is playing the screen changes to image that says "Commercial Break" and obnoxious music repeatedly plays. Once the add time is up, it goes back to the program. I know adds are themselves a pain, but this is worse. I see it while on some channels on YouTube TV and also Bally Sports, again during commercials.
Cable-type channels often have ad spaces where the local cable company or streaming service like Roku can sell and insert local ads. Screens like you show are default screens inserted into those spaces reserved for the cable or streaming ads. When the cable/streaming service inserts an ad it replaces that screen. If they have not been able to find an ad purchaser for that slot, you get that default "place holder".