Billionaire Ron Baron, a major Tesla shareholder, told CNBC on Friday that Elon Musk doesn't need "adult supervision."

"Are you kidding me? When all of a sudden you have this success? He could have retired when he was 30, 32 when he made $150 million, he chose to put all that money into SpaceX and into Tesla," Baron said in a "Squawk Box" interview from his annual investment conference at the Metropolitan Opera House in New York.

"This guy is worth $30 billion, $40 billion," Baron said two days after Robyn Denholm was named to replace Musk as Tesla chair. Musk was forced to relinquish the chairmanship in the wake of his infamous unfounded tweet that he had backing to take the electric auto maker private. Musk remains CEO.

"You need adult supervision?" Baron continued. "There's one Elon Musk. There's one Warren Buffett. There's one Jeff Bezos. There's one Sam Walton."

Tesla critics suggest that Denholm, a director there since 2014, does not count as the "adult supervision" they believe that Musk needs.

Meanwhile, Baron said he doesn't know Denholm, but expects to meet her next week.

He also said he's a "fan of women" in business. "[GM CEO] Mary Barra has done an amazing job." Women "think differently" than men, he added. He also credited women at Baron Capital who have "done an amazing job."

Musk has done phenomenally well with Gwynne Shotwell as president and COO of SpaceX, the entrepreneur's privately held commercial space company, Baron said, adding he hopes Denholm will be like Shotwell.

Tesla on Wednesday announced it elevated Denholm to chairwoman. Stripping Musk of the chairmanship was mandated as part of a September settlement with the Securities and Exchange Commission following his August tweets in which he claimed he had secured funding to take Tesla private at $420 a share.

During Thursday's trading session, Tesla eclipsed $357 per share, topping the $356.77 price when Musk sent those tweets. Tesla shares were down as much as 26 percent at their near-term closing lows on Oct. 19.

Last month, in his first CNBC appearance since Musk's erratic behavior over the summer, Baron told "Squawk Box" that he believes Tesla could be a $1 trillion company in revenue by 2030.

Baron reiterated that prediction on CNBC Friday, and added "maybe a $2 trillion in valuation" someday.

The Baron Capital founder said his average cost of acquiring his Tesla stake between 2014-2016 stands at $219 per share. Baron Funds currently owns 1.7 million shares, worth nearly $600 million at Wednesday's close of $351 per share.