As the horrors of last weekend’s attack on Israel by Hamas unfolded, people all over the world frantically searched for accurate information.

If they thought they could find it on what used to be Twitter, they were quickly disillusioned.

“The site is quite literally a war zone” is how the NBC News reporter Ben Collins describes what’s now called X.

Search for Israel or Hamas and you’ll find yourself in a cesspool of deepfake images, video-game clips presented as real-time footage, and straight-up lies.

In one case, an account that looked like the Jerusalem Post circulated the lie that the Israeli prime minister had been taken to the hospital, garnering hundreds of thousands of views. In another, a false claim went viral about Israel bombing a church in Gaza. Wired magazine reported that users were shown a faked picture of Cristiano Ronaldo holding the Palestinian flag, and a three-year-old video from the Syrian civil war presented as if it had just happened.

There is accurate information mixed in, but it’s increasingly hard to tell.

“Any truth is so decontextualized that you don’t even know,” Collins told me on Monday.

The trip to the social media gutter has happened with lightning speed. Elon Musk completed his acquisition of Twitter for $44bn a year ago this month amid predictions that the site would suffer on his impetuous watch.

The loss of what was an indispensable, if imperfect, social media platform would be bad enough.

But making the situation worse is that Musk apparently has done it all on purpose or at least with reckless disregard for his responsibilities to the common good.

Two factors dominate the mess, and neither of them has happened by mistake. One is the matter of what gets promoted by the platform’s algorithms in order to monetize certain posts, such as the supposed church bombing. Musk dismantled Twitter’s verification system, in which a check mark denoted a verified source, such as a prominent public figure or a news organization. That practice alone would have prevented the faked-up Jerusalem Post story from getting the traction it did.

Now the blue checks go to not to verified users but to those who pay for them, including many bad actors. X’s algorithm sends those posts to the top of its feed, flooding the zone with garbage.

The other big change is the sharp decline in internal efforts to fact-check or verify information. Not long after buying Twitter, Musk got rid of most of the Twitter content moderation staff that had tried to keep things as accurate as possible by flagging fake accounts and attaching warnings.

Then, in very recent months, according to the Information, Musk’s site stopped using a software tool used to identify organized misinformation.

The author and historian Ruth Ben-Ghiat reacted bluntly to that revelation: “Evil.”

Over the weekend, Musk added to the wartime chaos personally, urging his 150 million followers to heed two accounts notorious for spreading vile lies. He later deleted that post, but by then the damage was done.

There’s an ethical issue here that shouldn’t be ignored.

“Social media companies, particularly those that style themselves forums for free speech, have a moral obligation to try to ensure the free flow of reliable information to desperate users facing mortal risk,” said Suzanne Nossel, chief executive of PEN America, which advocates for free expression. Musk, she told me, has turned his back on that.

Bad as things are, they are likely to get worse.

As Hamas announced that it intends to begin killing civilian hostages and broadcasting executions in audio and video, Clara Jeffery, editor-in-chief of Mother Jones, foresaw more trouble: “I want everyone to realize that Elon has set up his site so that these snuff videos will be monetized for his blue checks.”

Jeffery offered advice to users who want to stay on Twitter, for whatever reason, on how to avoid having those auto-playing videos shoved into their feeds.

For some, it still makes sense to stay on X because its critical mass of users, including historians, journalists and news outlets, is still there. But the wisest do it with more skepticism than ever before, and with one eye on the door.

“Well, I think my time here is done,” posted Princeton history professor Kevin Kruse, whose insightful contributions amassed almost half a million followers on Twitter. “I’ve been telling myself for months that the good here outweighs the bad but I don’t believe that anymore.” Kruse said Tuesday that he would leave his account up but would decamp to two other sites: Substack and Bluesky.

He’s far from alone, and so the chaos grows.

Twitter’s accelerating demise is not, by any means, among the worst atrocities of the past week.

But, at a crucial time, it has managed to add to the world’s misery.

• Margaret Sullivan is a Guardian US columnist writing on media, politics and culture