Why in the world should Apple try to enter a well-established market which is already saturated with perfectly fine products, especially if they can't bring in their product at an attractively lower price (and we all know they can't or at at least won't)? If true, this seems to make zero business sense. Apple is always at its best when it dreams up some new category of product and can benefit from a period of months when it enjoys a virtual monopoly because absolutely no competition yet exists. Here we have an idea which is the exact reverse of that.
If Apple does want to get further into the audio-viz market, it could always market a dongle that you could plug into the audio jack of any teevee, amplifier or whatnot which would make it accessible to AirPlay and therefore a functioning part of Apple's "ecosystem." In other words, completely demolish the outer perimeter of that stupid walled garden they insist on maintaining. This would, inter alia, make the HomePod speakers available for anybody's video or sound setup, and I don't see how that would do any harm to the sales figures for that product, which evidently could stand improvement. As it is, the "walled garden" limitations of AirPlay severely restrict their usefulness and therefore their appeal to potential customers.