It is clear that Holden is a more-than-average cynical young man in this book and in this chapter, as he takes his date, Sally, to see a play with a famous couple called the Lunts in it, it is clear that he is definitely not impressed with what he sees. Although Holden says that the show was not terrible, he also says that it was a bit "on the crappy side" and that he is unable to become interested in the fate of any of the characters. Apart from the expected criticism of it all being phony, note what he has to say about the star couple themselves:
They didn't act like people and they didn't act like actors. It's hard to explain. They acted more like they knew they were celebrities and all. I mean they were good, but they were too good... If you do something too good, then, after a while, if you don't watch it, you start showing off. And then you're not as good any more.
Even though he does credit the couple as being the only actors with any "brains," it is clear that the fact that they are "too good" at what they do means that they do not impress Holden, who seems to have set himself and others impossibly high expectations to meet and follow.