Judd Apatow’s “Funny People” starred Adam Sandler as George Simmons, a once-dynamic stand-up whose comic mojo has grown bloated and blunted after starring in a series of hit movies and ensconcing himself in a luxurious mansion.

Apatow’s latest, “This Is 40” -- about the financial and romantic foibles of a well-off couple hitting a milestone birthday -- feels like George might have written it, or at least directed it.

The bawdy wit and crisp dialogue that were the hallmark of Apatow’s “Knocked Up” (of which this is a quasi-sequel) and “The 40-Year-Old Virgin” are still very present, but the conflicts feel so cushy, so first-world, that one gets the impression that the filmmaker is losing touch with life as it is lived outside of Brentwood.

Not that the wealthy and the privileged can’t have problems of their own, or can’t be the subjects of drama, but when characters who drive BMWs, hang pricey contemporary art throughout their spacious house, go on spa weekends, cater lavish parties and have a seemingly endless supply of Sprinkles cupcakes in their kitchen, it’s a little hard to be sympathetic when those same characters wail about their money woes.

I was reminded more than once of “Spanglish” (also, coincidentally, starring Sandler), another frustrating movie about privileged L.A. folk, a film that made me want Cher’s character from “Moonstruck” to suddenly manifest so she could smack all the characters in the face and say, “Snap out of it!”

“Knocked Up” sideline characters Pete (Paul Rudd) and Debbie (Leslie Mann, Apatow’s wife) return, facing the big 4-0 among other challenging issues in their life. Pete left his gig at Sony a few years ago to start an indie label for niche acts, and after shelling out for a new album by Graham Parker (playing himself throughout, with good cheer), the record’s not selling.

Debbie’s boutique (selling what the ladies of “Absolutely Fabulous” would call “gorgeous things”) has a $12,000 shortfall, although she’s so obsessed with her age that she never seems all that upset about the missing cash. (Again, these are very niche economic problems.)

While Pete tries to figure out how he can avoid losing the house, while still giving money to his dad (Albert Brooks), Debbie avoids telling her husband the bombshell news that she’s pregnant. Meanwhile, their young daughters (played by Mann and Apatow’s kids, Maude Apatow and Iris Apatow) are constantly squabbling, and Pete and Debbie find it tricky to lay down the boundaries when they’ve got vices of their own. (Debbie still secretly stress-smokes; Pete can’t stop eating those cupcakes.)

As with most Apatow movies, “This Is 40” works best when characters are talking to each other about the real day-to-day mechanics of relationships, friendships, sex, aging and other relatable concepts. He’s a master at crafting dialogue that’s obscenely hilarious and blisteringly honest at the same time, and that gift hasn’t eluded him.

But so much of the film centers around Paul and Debbie’s privileged trappings (the trainer! the iPads!) and their impotent attempts to deal with it, that it’s often like being trapped at a restaurant next to a table of people clucking about how you can’t find a good nanny these days. And that’s a shame, because it’s a waste of some very talented performers who nonetheless give the material everything they’ve got.

Rudd’s one of those comic actors who makes it all look effortless, but with very little fanfare, he’s becoming one of our most reliable leading men. For her part, Mann makes her character palatable, despite a few too many screechy moments, and her comic timing is so precise you could set your watch by it.

They’re ably supported by a strong ensemble, from the Apatow sisters (very convincing as combative siblings) to Brooks, Robert Smigel, Jason Segel (as Debbie’s semi-smarmy trainer), John Lithgow, Melissa McCarthy (hilarious as an enraged mom), Chris O’Dowd and Megan Fox (whose sense of humor and ability to be in on the joke when men around her are swooning over her body make her the millennial Jayne Mansfield — and I mean that as a high compliment).

Absent, if you were wondering, are Seth Rogen and Katherine Heigl from “Knocked Up,” with nary an explanation.

If Apatow’s previous movies have made you laugh, then “This Is 40” certainly will as well. But those moments of great comedy are stuck together by a worldview so cosseted that it threatens to muffle an exceedingly talented screen artist.