“I wouldn’t be surprised if he is withholding his voice from Twitter out of some principle,” Jason Goldman, a member of Twitter’s founding team who has also served on its board, said of Mr. Dorsey’s recent actions. He added that in his latest comments, Mr. Dorsey “acknowledges how poorly things have gone for Twitter under Elon Musk.”

Mr. Dorsey and Mr. Musk did not respond to requests for comment.

Mr. Dorsey, who helped found Twitter in 2006, was the company’s chief executive for eight years over two different stints. And while the social network’s success turned him into a billionaire, he appeared to become disillusioned in recent years with Twitter’s direction.

Among other things, Mr. Dorsey, who supports free speech, lamented that Twitter had become too powerful as an arbiter of what kind of posts should stay online and what should be pulled down. He also blamed Wall Street for turning Twitter away from its primary role as a communications platform, pressuring it to make money and to eventually sell itself to the highest bidder.

In November 2021, Mr. Dorsey, who also leads the payments start-up Block (formerly known as Square), stepped down as Twitter’s chief executive. He left its board last year after Mr. Musk bid for the company.

Mr. Dorsey has since said that Twitter should have been built as a different kind of social network: a decentralized one. Unlike mainstream social platforms, which run private code that they control, decentralized social networks make their systems public so users can potentially build their own apps and communities. That way, no single entity can impose rules on what can or can’t be said in these networks, and users can customize their experiences.