We all hear it, particularly if you regularly interact with Austinites over about the age of 40: some variation of the perception that ACL (and popular music in general) are leaving rock ‘n’ roll behind, or words to that effect. It’s dead. The kids don’t like it — “kids these days.” Variations on that theme.

If you’re among those who fret about that, Saturday’s lineup was bookended with loud, guitar-heavy reminders that rock is still Zilker-approved — respites from your Sabrina Carpenters, Doechiis and, hell, maybe even the Mag Bays, with their pop processing, electronics and general lack of downtuned, angular guitar rumble. Yes, Grandpa Simpson, rock is still alive — and what’s more, “the kids” are still into it. (Sorry … Homer Simpson was famously the more appropriate choice there.)

The best rewards along these lines came from getting there early enough on Saturday — while the weather, true to form, was obnoxiously hot — and staying late enough. And the deliverers of those rewards were both New York bands, old money and new money. Appropriately enough, during Hotline TNT’s 12:45 set, frontman Will Anderson asked his crowd,  “ACL, you guys like real guitars? Then make some noise.” Indeed, Hotline (top photo) is a dyed-in-the-wool alternative guitar band — and a talented one, churning out crunchy, dense and dark rock songs with a moody kick. Their set Saturday carried great appeal for anyone who thinks rock either began or peaked at Nevermind or Siamese Dream — in fact, some of lead guitarist Lucky Hunter’s riffs sounded straight down the family tree from Billy Corgan. Songs like the rocker “Candle” and the shoegaze-y “Protocol” left a strong impression. Interestingly, Hotline stuck entirely to the music, without any societal commentaries or philosophical musings — perhaps a little surprising for one of the bands that recently pulled its music from Spotify.

It’s impossible to know how many people who saw turn-of-the-century rock legends the Strokes at headline time were also in Hotline’s solid-for-12:45 crowd. But to whatever extent there was overlap there, the rockists among them had to have ended their nights happy — because Julian Casablancas, Albert Hammond, Jr., Nick Valensi and crew emphatically proved they can still rip it. Stampeding with admirable force through all their big ones — “Someday,” “Reptilia,” “Last Nite,” “Take It Or Leave It” to close — NYC’s favorite sons of roughly 2001-05 betrayed no dropoff either in energy or skill, and Casablancas still possesses every inch of that voice that shifts between drowsy and shouty like almost no one’s in rock history. (Notably, the disinterest among youth for rock music is greatly exaggerated, judging by the amount of visually under-30 concert goers at both the Hotline TNT and Strokes shows.)

Another thing Hotline’s Anderson asked his crowd during the afternoon set was, “Austin, do you fuck with us?” The response was loudly in the affirmative. Yes, Austin — and Austin City Limits — still fuck with rock ‘n’ roll in its best forms. So does the world.