Charles McGrath writes in the NYTimes about what PBS is doing wrong and what NPR is doing right. And why, perhaps, PBS is permanently past its prime and we should pull the plug. His argument that cable TV has supplanted many of the kinds of shows pioneered by PBS is offered somewhat regretfully, but it has been heard before — primarily from staunch critics of federal funding of public broadcasting.

I’ve always felt there are two weaknesses with this argument: First, it’s rather class-biased. It assumes Americans no longer need PBS because everyone pays for cable TV — they don’t, not by a long shot. In fact, for all of Mr. McGrath’s talk of PBS’ audience declining (with the implication that viewers have been fleeing to cable), last year saw a drop in viewership for cable news, while cable subscribership in general has more or less hit a plateau since 2003. According to State of the News Media, the combined viewing audience for all of the prime-time cable news channels is 2.5 million. Or only about one million more than PBS’ single channel of evening programming. That’s not exactly an overwhelming domination of the airwaves.

Second, the kinds of PBS shows that are typically cited here — nature documentaries, history specials, biographies, NOVA, political news — have indeed been glommed on to by the Discovery Channel, History, National Geographic and the rest. What’s rarely cited are either programs such as POV and Frontline, news documentaries that take the kind of risks commercial television news simply won’t, or serious arts programming.

When it comes to cultural shows, Mr. McGrath contrasts the heyday of Monty Python and Upstairs, Downstairs to today’s schedule of Antiques Roadshow and Masterpiece — whose costume dramas are copied (or done better) by a half-dozen Hollywood films and Showtime’s The Tudors. What’s never mentioned are series such as Live from Lincoln Center, Simon Schama’s Power of Art, Charlie Rose, ART:21 or Kennedy Center Presents.

Whether you value all of those shows or not, you can scour the entire cable universe and find almost nothing like them. A prime example is the jocularly named cable channel A&E. It never seems to schedule a single program devoted to any actual art form, unless it’s neo-classic bounty hunting (Dog), post-modern car impounding (Parking Wars), ESP investigations (Paranormal State) or the traditional art of the televisual rerun (CSI, The Sopranos). I would argue that one thing PBS seriously needs is more arts programming — simply because, much as with Frontline, no one else is doing it.

This post isn’t meant to be a defensive bit of PBS cheerleading. In fact, much of what Mr. McGrath says about the network’s aging demographics and aging franchises (The NewsHour, The American Experience) and its recent, imitative ways (America’s Ballroom Challenge) is uncomfortably true. But he also makes this point: “Considering how much it costs to create new topnotch programming, the best solution to public television’s woes is the one that will probably never happen: more money, not less.”