I don't think it's necessarily avoidance behavior, but excessive use of ambient TV may be avoidance behavior.

For example, my girlfriend experiences tinnitus, so having a completely silent house is annoying to her, since she just hears a high pitched noise instead of silence. But if you use ambient TV to avoid getting lost in your own thoughts because of fear of where they might take you, or if you use it as a stand-in to avoid feelings of loneliness for actual human company/conversation, then that is where I see it as unhealthy.