What just happened? They may both be billionaires, but Elon Musk and Bill Gates are not the best of friends. The latest spat between the two relates to the former's acquisition of Twitter, which the ex-Microsoft boss has warned could make the platform "worse."

As reported by CNBC, Gates was speaking at the Wall Street Journal's CEO Summit Wednesday about Musk's takeover of Twitter. Much of what he said related to the Tesla boss' claims that he would reduce moderation on the platform and embrace the principles of free speech.

But Gates questioned Musk's plan and his ultimate goal for Twitter. "How does he feel about something [on Twitter] that says 'vaccines kill people' or that 'Bill Gates is tracking people?'" Gates asked. "What are his goals for what it ends up being? Does that match this idea of less extreme falsehoods spreading so quickly [and] weird conspiracy theories? Does he share that goal or not?"

Musk has talked about his desire to make Twitter a bastion of free speech by taking a more relaxed approach to moderating tweets, though it looks like the EU will have something to say about turning the site into a free-for-all. He also wants to get rid of the platform's bot problem and open-source Twitter's algorithm.

Gates did have some praise for Musk, though. He called his time at the head of Tesla and SpaceX "mind-blowing" and said he did a good job of putting together great teams of engineers at those companies.

"I kind of doubt that will happen this time [at Twitter], but we should have an open mind and never underestimate Elon," Gates added.

Musk has also talked about his ideas for increasing Twitter's profitability, including charging for embedding tweets and making businesses and governments pay to use the service.

Musk confirmed last month that he had confronted Gates about shorting Tesla stock, which he followed with a Tweet mocking Gates' appearance. It marked the latest clash between the pair, following public disagreements over Covid-19, colonizing Mars, and cryptocurrencies.