There is only one Marcus Mumford — and earnest ballads like “Guiding Light” mean something to many. Sunday night at an Austin City Limits Music Fest-closing performance, he also closed a decade as one of rock’s most influential frontman.

“We came back with some newer songs,” he said before “Beloved,” a tightly written and difficult-to-dislike gem from his band’s most recent record, “Delta,” released almost a year ago in November.

In 2016, the band delivered a punchy set here as a defiant stand against those who write off Mumford & Sons as ripoff artists who oversimplified Americana for arenas. That may be true for Mumford sons like Of Monsters and Men, American Authors, and the Lumineers, but Marcus oozes charisma and writes memorable affirmations.

Someone please paint “Even when there is no star in sight, you’ll always be my only guiding light” on a block of wood and sell it on Etsy.

At ACL Fest, they got to it. “Little Lion Man,” 2011’s breakthrough acoustic jam, saw the band return to its banjo-and-bass roots as a huddled, buskering four-piece on the American Express stage’s catwalk one song in. They’d return to the catwalk to harmonize around one mic an hour or so later. The Mumford boys found intimacy, though that proved easier than expected because Zilker Park wasn’t too busy. I was able to walk to the stage-right fence minutes before start time with no elbowing, and for the first time during an ACL Fest headliner this weekend, I enjoyed cell service deep in the crowd.

“This is a bit overwhelming man, there’s so many people here,” Mumford said, contradicting my anecdotal assessment but also correct given the scope of the fest, and asking folks to hold up lighters before the inward-gazing “Believe.”

I’ve been brushing up on my discography and, as George Michael put it, listening without prejudice. All the dude writes is big choruses — the only true blunder tonight was that their enduring radio tune “The Cave” dragged tempo-wise. But Mumford adds weight and soul to easy-listening and simple-plucking ballads like “Ditmas.”

“It’s starting to feel dangerously like home,” Mumford told locals. “A familiar smell of barbecue, beer and weed all mixed together.”

He later said he wished he was watching Cardi B and, like 2016, said ACL Fest was maybe the best festival in the world.

Here the band was nine sons strong. The core four of Mumford, keyboardist Ben Lovett, banjo bro Winston Marshall, and bassist Ted Dwane were amplified by five riser-relegated instrumentalists and percussionists. The added personnel came to life on the post-rock experimenting “Darkness Visible.”

Mumford, in a snazzy black vest, was everywhere tonight — playing drums on “Lover Of the Light,” on acoustic and electric, in the audience.

They said they’d soon release deep cup “Blind Leading the Blind” and tonight they were recording a video for it. They said they enjoyed and made time for Childish Gambino on Saturday night.

Ninety-plus minutes of Mumford & Sons is a heavy prescription to fill for a band with two recent albums not as commercially beloved as the first one. And after “I Will Wait,” many patrons headed for the shuttles.

“We’re Mumford & Sons and we’re grateful,” Mumford said at 9:40 p.m. as the show ended.

How can anyone not like this guy?