I anticipated the analogy to the Golf Channel. I don't see tennis as having the same appeal. You might be right, perhaps they will endure with tennis only content. I don't agree, but time will tell.
Golf is probably a bit ahead of tennis at present, mainly for jingoistic reasons -- it has more American stars than tennis, and domestic names on the leader board generally attract more interest, whether one approves of that or not. (I'm speaking, of course, of the men's game. The women's game has been dominated by Asian players, mostly Korean, for the last decade or so, with a sharp fall-off in interest by Americans.) Jordan Spieth's hot stretch last year jacked up ratings nicely for a while. Imagine what a rivalry with a charismatic American rival would do -- but a declining Mickelson and an apparently spent Woods can't fill that role anymore.
In men's tennis, John Isner is the leading American by default, and he is a powerful but lumbering, one-dimensional player who has never gotten a sniff of a major title. In most tournaments, he is gone before the semifinals, which means little TV exposure except to the hardcores. The top names are all European. Women's tennis has been perceived for years as the Williams sisters and a bunch of "-ova"s. Other than Venus or Maria Sharapova (a rare recognizable "-ova," but now facing a lengthy ban from the sport), who would anyone go out of his or her way to watch Serena play?
Basically, though, both are niche sports that occasionally capture the American public's imagination through the play of American players with style, charisma and/or attitude as well as great talent. Spieth is no Woods yet, but he's closer to that level than Isner or any of the other US men currently playing ever will be. Still, all it takes is one or, preferably, two best-of-generation American tennis players to make the game relevant to mass audiences again.
