Elon Musk says users on X, formerly Twitter, will lose ability to block unwanted followers, eliminating key safety feature

Users of X, formerly known as Twitter, will no longer be able to block comments from unwanted followers, according to a post by X owner Elon Musk on Friday, eliminating what's long been viewed as a key safety feature. Blocking will only be available for direct messages, he said.

"Block is going to be deleted as a 'feature', except for DMs," Musk wrote Friday. He was responding to a post from the account of Tesla Owners Silicon Valley, asking, "Is there ever a reason to block vs mute someone?" The group behind that account promotes the electric car company, where Musk is CEO.

Since acquiring Twitter last year for $44 billion, Musk has overhauled the company, laying off many employees, reinstating previously banned accounts and recently rebranding the company and platform as X. He didn't provide a reason or a time frame for eliminating the block function, only saying in a follow-up response that "it makes no sense" and that the mute function will still be available.

Users have been able to use the block function to make sure that hateful content and harassment doesn't show up in their feed in response to their posts. The mute feature just keeps the individual user from seeing the undesired responses, but doesn't eliminate them from others' feeds.

Twitter users have also long employed the block feature in boycotts and to avoid seeing ads from specific brands or promoters on the platform.

Binance CEO Changpeng Zhao, an investor in the new Twitter alongside Musk, said in a post that the company should focus its attention elsewhere.

"X should really solve the bots & spam problems before removing blocks," wrote Zhao, whose company owns one of the world's largest crypto exchanges. "Just my 0.02."

Louis Jones, a longtime media and advertising executive who now works at the Brand Safety Institute, said Musk's latest plan is very concerning as users could be inundated with spam, threats and other harmful content.

Musk's "lax approach to free speech," is likely to have a "double effect," making bullying more common on the platform and inhibiting free speech by those users who are targets of bullies and predators, Jones wrote in an email to CNBC. "It's a downward spiral that cannot be good for the long term success of X."

— CNBC's Lora Kolodny contributed to this report.

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