The whole thing is strikingly measured. It is her biggest shift in tone since the one-two punch of “We Are Never Ever Getting Back Together” and “I Knew You Were Trouble,” in 2012. But those songs were boisterous and savvy iterations of ideas she’d already been exploring. “Look What You Made Me Do,” by contrast, is a gut renovation, and shows that Ms. Swift is willing to incinerate herself if that’s what it takes to burn everyone else.

WESLEY MORRIS Gang, we are gathered here today to celebrate this thing called strife. And I’m bummed. There’s no room, in this rendition of strife, for the usual shading and wit and flexible scale of Ms. Swift’s songwriting. She’s so good at petulance, spite, comeuppance and denouncement. She’s even better at a kind of pop song that’s harder to pull off, but that the greats, from Aretha Franklin to Fiona Apple, achieve with sneaky ease, which is mutual recrimination: We’re both fools! That emotional dexterity is on a break.

Vengeance might be on Ms. Swift’s mind right now, and not because she loves herself some Carly Simon (well, not only that). She just won a sexual assault case that she’s held up as victory for all women, on the one hand. She’s been in an unflatteringly comical fight with Ms. Perry, on the other. “Vengeance” sounds petty and vindictive here. As it is, that title is more or less what Kathy Bates screams at James Caan not that long into “Misery.” But it’s also music (and titling) that seems defensive, wittingly or not, at pop music as much as any one pop star. This song doesn’t sound felt. It sounds compelled to matter. It sounds cynical.

When Taylor declares herself — the old her — dead via phone call, in the breakdown, it gave me the “13 Reasons Why” blues. (Good luck with that, America’s middle-school administrators!) I much prefer the violence in a song like “I Knew You Were Trouble,” where she’s melodically evocative about the physical state of being hurt.

“Flew me to places I’d never been

’Til you put me down, oh

I knew you were trouble when you walked in

So shame on me now

Flew me to places I’d never been

Now I’m lying on the cold hard ground”

Also: What a fun song to sing. Even in the pain, there’s a kind of ecstasy. I’ve listened to “Look What You Made Me Do” five times now, and I don’t hear that. I hear Ms. Perry, Peaches, Lorde, Fergie, J.J. Fad, and, lord help me, J.J. Fad courtesy of Fergie. What I can’t hear is Taylor Swift. Just about all her peers can speak electropop fluently. She’s doing remedial exercises on this one, and all I hear is her cramming.

CARYN GANZ It’s fury, it’s vengeance, it’s gossip. It’s a horror movie, a fairy tale contorted into a calamity. Musically, it’s a pubescent growth spurt — sudden, jerky and accompanied by a sneer.

“Look What You Made Me Do” feels like pure calculation: This one isn’t for the moms toe-tapping at the “1989” concert, or the radio stations still chin-scratching over whether Ms. Swift is country or pop. This song is for the base — the superfans on the internet who are always ready for a fight.