"Writing for the majority, Justice Amy Coney Barrett said companies such as Facebook and YouTube have long-standing content-moderation policies that place warning labels on certain posts and delete others."

"The challengers, Barrett wrote, did not demonstrate that the companies’ actions to remove posts were traceable to the government. Barrett said a lower court got it wrong when it 'glossed over complexities in the evidence' by attributing to the Biden administration every company decision to remove or moderate content. 'While the record reflects that the Government defendants played a role in at least some of the platforms’ moderation choices, the evidence indicates that the platforms had independent incentives to moderate content and often exercised their own judgment,' she wrote."

From "Supreme Court allows White House contacts with social media firmsIn a 6-3 ruling, the majority said the challengers did not have legal grounds — or standing — to bring the case against the Biden administration" (WaPo).

ADDED: Here's the NYT piece, by Adam Liptak.

“The plaintiffs, without any concrete link between their injuries and the defendants’ conduct, ask us to conduct a review of the yearslong communications between dozens of federal officials, across different agencies, with different social-media platforms, about different topics,” Justice Amy Coney Barrett wrote for the majority. “This court’s standing doctrine prevents us from exercising such general legal oversight of the other branches of government.”

Justice Samuel A. Alito Jr, joined by Justices Clarence Thomas and Neil M. Gorsuch, dissented.

“For months,” Justice Alito wrote, “high-ranking government officials placed unrelenting pressure on Facebook to suppress Americans’ free speech. Because the court unjustifiably refuses to address this serious threat to the First Amendment, I respectfully dissent.”

AND: Here's the text of the opinion.  The case is decided on the threshold issue of standing, so the majority does not reach the merits of the First Amendment question. The plaintiffs were seeking prospective relief, so they needed a concrete and particularized injury that would be redressable by that form of relief. Past injury is not enough:

Lyons is a well-known case, reviled by liberals, in which a man who was choked nearly to death by the police was held to lack standing to seek an injunction restricting police chokeholds. His injury was in the past, so he had standing to seek damages, but prospective relief is another matter, and the fact that no one knows the identity the future victims in advance did not change the analysis. Standing is a constitutional requirement, and if you don't have it, you don't have it. Let the chips fall where they may.