Amid the incalculable losses of the pandemic, live music might seem trivial to some. But at their largest — with thousands of young people, pure of heart and purpose, screaming and stomping, mobilizing air and shaking concrete — concerts can shock, awe and inspire. On Saturday night at the Capital One Arena, a capacity crowd broke its 18-month fast and returned to the collective communion of a live concert, thanks to Harry Styles.

As the audience buzzed with anticipation, the first test of its noisemaking abilities came early, when a prerecorded message from Styles thanked attendees for being vaccinated against or testing negative for the coronavirus, a condition for entry. That received a big cheer, as did his ask for people to keep their masks on, due in no small part to the flirty postscript: “I’ve always found you can tell the most about a person from their eyes, anyway.”

That charm and the ecstatic response were hints of what was to come.

The crowd erupted when the 27-year-old heartthrob took the stage, decked out in cream boots and periwinkle bell-bottoms, tattoos peeking out of the sleeves of his floral shirt. Backed by a six-piece band, Styles launched into “Golden,” the sunny opener to his 2019 album “Fine Line” — a total pro surrounded by the same.

Styles was trained by the boy-band machine, and his charisma was undeniable as he floated across the stage, dodging sunflowers and the odd inflatable watermelon (both nods to his song titles) thrown by fans. When he explained what performance in the round would entail for the view — sometimes his face, sometimes “all bum, baby” — the well-practiced line had the intended swooning effect.

Early in the night, Styles entreated the crowd to have as much fun as possible and to be whoever they wanted to be. He seemed to be having fun, too, but who does he want to be?

“Fine Line” wears the same period-appropriate costume that Styles did Saturday. While the lithe grooves of songs such as “Adore You” and “Lights Up” make them absolute pop smashes, too often Styles leans heavily on his classic rock influences, evoking better songs by the Beatles, Elton John or Pink Floyd. His fans would clearly follow him anywhere; hopefully, he’ll one day take them to the future.

In other ways, Styles is entirely of the moment. During the feel-good anthem “Treat People With Kindness,” the singer lapped the stage while waving the flags for gay pride, transgender pride and the Black Lives Matter movement. The song’s sentiment is anodyne, but cynicism seems lazy, especially at a concert that took place just a few hours and blocks removed from a small gathering of protesters demanding the release of Jan. 6 rioters. So maybe Styles and his fans are ready for the future, even if his music still sounds like the past.