WASHINGTON: Twitter said it permanently suspended Donald Trump's account after the January 6 Capitol riot because there was a risk of further incitement of violence, following months of tweets disputing Joe Biden's presidential election victory.

False and misleading claims about American politics have since plummeted, a trend Twitter and Facebook -- which also blocked Trump but may reverse course -- are keen to take credit for.

With Trump muted, a comparatively media-shy Biden in the White House, and no election cycle underway, Americans remain interested in economic recovery and a Covid-19 vaccine rollout but are not as consumed by politics as they were in 2020.

It is that shift in the news cycle, rather than any fundamental change in how people spread inaccurate information, that is responsible for a lower volume of political falsehoods, experts say.

"The single most important thing was de-platforming Donald Trump," according to Professor Russell Muirhead, co-author of "A Lot of People Are Saying," a book title that plays on one of Trump's most popular sayings, used when promoting unproven theories.

"It has removed a daily blizzard of misinformation from the ecosystem," Muirhead told AFP. "Not being bombarded is helping people's misinformation immune systems to reset themselves and recover."

But the effect is likely temporary in an online environment where news shapes misinformation. Conspiracy theories about vaccines, for example, have flourished in 2021.