Baby boomers have been enjoying a love-in with David Letterman this month. And next month they’ll get their ya-yas out with the Rolling Stones in concert. Aren’t Gen-Xers entitled to nostalgic fun, too? They got their chance Wednesday night at Xcel Energy Center with a triple bill featuring New Kids on the Block, TLC and Nelly.

New Kids, who ignited the boy-band craze in the late 1980s and early ’90s, have been on the comeback trail since 2008. In 2011, they wove together a brilliantly choreographed concert tour in which they literally shared the stage with Backstreet Boys, a next-Gen boy band. In 2013, NKOTB toured with 1990s vocal group Boyz II Men but they didn’t perform together.

On Wednesday, NKOTB proved why they are the undisputed kings of (living) boy bands — as they were so introduced for their boxing-themed Main Event Tour — as well as champs of how to stage a show.

Forget about Nelly, an ’00s rapper with sing-songy rhymes, bulging muscles and a month-old arrest on drug and weapons charges. Forget about TLC, the ’90s pop-soul trio trimmed to a duo that is making its first tour since the death of Lisa “Left Eye” Lopes in 2002. Not only were Tionne “T-Boz” Watkins and Rozonda “Chilli” Thomas lip-syncing much of the time (with Left Eye appearing via recorded raps) but they had about as much chemistry as ex-partners who share nothing but a bank account.

Then there was New Kids, who looked like they were having as much fun as the 12,000 women (and 19 guys) in the audience. Their material may be hopelessly derivative pop-soul music (the ballads sound like the Stylistics, the up-tempo tunes like generic dance-soul/disco) but these forty-something guys know how to put on a show and clearly enjoy doing it.

Over the course of two- dozen songs and two hours, NKOTB worked it, with infectious energy, slick but simple dance steps, varied staging on three connected stages (loved the five pedestals with the adjusting heights), whiz-bang effects (the explosions, confetti and streamers during the first five songs felt like a Kiss encore) and a campy, let’s-have-fun attitude.

The show started with all five New Kids in a filmed commercial for a brand of toilet paper. (A first in the music business, no doubt.) After the first five songs, live video cameras followed the singers into “quick change rooms” under the in-the-round stage where fans could watch them change into suit and ties (for inquiring minds who want to know, they all wore black boxers).

As Joey McIntyre sang a romantic ballad, he held a woman’s hand and then kissed it. All five singers ventured into the crowd during “Tonight,” one of those peppy, mindless jock-jam type songs. Danny Wood did some break-dancing. Jordan Knight unleashed his falsetto on several tunes. And Donnie Wahlberg, the only New Kid with a current career (he’s an actor, currently on CBS’ “Blue Bloods”), even did a taste of his brother Marky Mark’s old hit “Good Vibrations.”

The giddiness of so many thirty- and forty-something women getting in touch with their 10-year-old selves couldn’t be denied. It makes you wonder how, in a few years, millennials will react to the One Direction reunion tour with Zayn Malik.