The bombshell antitrust lawsuit filed by Elon Musk’s X against a now-defunct advertising cartel and several brands accused of a collusive boycott was a critical step toward fixing a “broken” ecosystem, X CEO Linda Yaccarino said Tuesday.

In an interview with The Post, Yaccarino shed new light on X’s decision to wage legal “war” on the Global Alliance for Responsible Media, which was suddenly shut down days after the social media company filed its suit last week.

The left-leaning nonprofit and other defendants were accused of coordinating a boycott against X that cost the site “billions of dollars in advertising revenue.”

“We were victimized by a small group of people pushing their authority or ability to monopolize what gets monetized,” Yaccarino said.

“GARM was just a symptom, but [finding] the root cause of the entire ecosystem being broken, that’s what the suit is about.”

Yaccarino, the former top ad executive at NBCUniversal, said X’s goal is to bring “sunlight” to the problem and spearhead a shift toward greater transparency regarding the data and processes that advertisers use to determine where to spend their money.

“It’s about finding out exactly what happened and finding out why or where this was personal bias, which became the determining factor for advertiser investment,” Yaccarino said.

X’s lawsuit, filed in Texas federal court, will continue against GARM’s parent – the powerful World Federation of Advertisers, whose members control 90% of global marketing spending.

The WFA cited the nonprofit’s strained resources for the decision to shut down GARM as it contests the antitrust suit.

Aside from GARM and WFA, a handful of major companies — CVS Health, Mars, Orsted and Unilever – were named as defendants. X is seeking trebled compensatory damages and injunctive relief.

Yaccarino said the lawsuit arose as a “direct result” of evidence uncovered by the House Judiciary Committee, which accused GARM executive Robert Rakowitz and others of coordinating a campaign to restrict ads to a slew of news outlets and online platforms, including The Post.

The House panel’s report detailed one instance in which Rakowitz appeared to brag that X was “80% below revenue forecasts” since GARM targeted Musk over brand safety issues. Rakowitz told investigators the email was meant as a joke.

The House Judiciary Committee has since sent letters to more than 40 companies demanding they provide information and preserve evidence regarding any dealings with GARM.

While more legal action isn’t the company’s goal, X hasn’t ruled out the possibility of suing other companies if more evidence surfaces in the days ahead, Yaccarino said.

“I want to make it clear companies are free to make their own advertising decisions,” she said. “But when a small group of advertisers work together to coordinate a boycott. The law does not allow for that.”

Yaccarino insisted that X’s relationships with advertisers remain strong despite the ongoing legal battle, stating that “many people have reached out to me in support” since X announced the move.

The X boss pointed to several recent events that demonstrated the value of the site’s audience, including Musk’s widely-watched interview with former President Donald Trump on Monday night and President Biden’s decision to announce his withdrawal from the 2024 election by tweet.

Upcoming product launches, such as X’s long-awaited payments processor, also will be attractive to advertisers, Yaccarino added.

“X has become something totally different in the last 18 months, and it’s become this indispensable platform where users around the world spend more of their time and their lives on the platform,” she said.

Yaccarino has navigated a period of intense turmoil since taking over as CEO in mid-2023.

The company’s struggle with an advertiser exodus intensified as Musk overhauled the business and concerns mounted that loosened content moderation practices had allowed the spread of antisemitic posts and other harmful content.  

Last fall, the situation grew so contentious that a group of advertising executives pushed Yaccarino to resign during a Nov. 18 conference call, according to multiple reports. Yaccarino confirmed the incident had occurred.

Despite the turmoil, Yaccarino said she is committed to X “more than ever” and excited about the company’s product pipeline.

“I’m exactly where I need to be,” she said. “And X sits at the epicenter of culture, and I’m here to drive business results for people.”