As a protest song, "Only the Young" discusses subjects such as school shootings, Donald Trump, and vote-tampering concerns in its lyrics.

Upon release, music critics praised Swift's lyricism on United States politics, addressing matters such as gun violence and mass shootings.

In an interview with Chris Willman of Variety, Swift revealed that she held back "Only the Young" from being included on her seventh studio album Lover (2019).

[2] Prior to the elections, Swift broke her political silence by endorsing two Democrats: Congressman Jim Cooper for re-election to the House of Representatives, and former Tennessee governor Phil Bredesen for the Senate.

And I found that to be particularly tragic, because young people are the people who feel the worst effects of gun violence, and student loans and trying to figure out how to start their lives and how to pay their bills, and climate change, and are we going to war – all these horrific situations that we find ourselves facing right now.Although Tennessee governor Phil Bredesen lost the Senate race against Marsha Blackburn, Swift helped to motivate young voters to get registered to vote.

She does this by alluding to 2017–2021 US President Donald Trump, the 2016 presidential election, the succeeding vote tampering allegations, and issues like gun violence and school shootings in the United States.

[13] Billboard's Gil Kaufman called the song an "urgent, clear-eyed" tune that sees Swift "giving voice to her disillusionment about our stuck society".

He described the theme as "a sad concession and a defiant warning" to older generations on how "their greed and failure to act has given rise to a youth movement determined to turn the page".

[14] Vulture's Zoey Haylock found the song to be urging the listeners to "get out there and participate in democracy", and added that it exudes Swift's faith in the American youth.

[10] Rolling Stone writer Claire Shaffer wrote that the song documents the singer's "recent political awakening" as seen in Miss Americana.

[18] Paper's Jael Goldfine defined the song as the musical accompaniment to Swift's "newly radicalized political identity"—"the Democrat-voting, Dixie Chicks-defending, nice-girl-no-more that she crafts in Miss Americana".

[12] Nylon's Layla Halabian termed the song a hopeful anthem "over a shimmering pop production", encouraging the youth to "challenge the establishment and secure a safer future".

[20] Michael Ordoña, writing for Los Angeles Times, listed "Only the Young" as one of 2021's Oscar-contending songs, remarking that it underscores Swift's status as a "significant cultural figure", evolving from her former "sugar-pop queen" image.

It opens with a quote from vice presidential candidate Kamala Harris wondering why "so many powerful people are making it so difficult to vote".

The rest of the video features a montage of "chaotic and hopeful" scenes from the past four years in the US: Clips of #MeToo and Black Lives Matter protesters, President Trump removing his face mask following a hospitalization for COVID-19, Judge Amy Coney Barrett being sworn in as a Supreme Court justice, a 75-year-old protester in Buffalo being pushed to the ground by police, and a scene of young voters and supporters of Democratic presidential nominee (and eventual winner) Joe Biden organizing and taking part in early voting.