Carmack is a legend in the gaming and virtual reality (VR) worlds, being cofounder of id Software, the firm that published the seminal Doom game. Eight years ago he became chief technology officer (CTO) at Oculus VR, the VR-headset outfit that Facebook—which was rebranded as Meta on Thursday to reflect its new focus—acquired soon after he joined. A couple years ago he stepped back into a consulting-CTO role. He’s highly respected to say the least, and he doesn’t think much of Zuckerberg’s plan.

“I want it to exist, but I have pretty good reasons to believe that setting out to build the metaverse is not actually the best way to wind up with the metaverse,” Carmack, who has been talking up the metaverse concept since the 1990s, said. The problem, he explained, is that the concept is a “honeypot trap for architecture astronauts…a class of programmers or designers that want to only look at things from the very highest levels.” Such people don’t want to talk about “any of the nuts and bolts or details,” he complained.

“But here we are, Mark Zuckerberg has decided that now is the time to build the metaverse, so enormous wheels are turning, resources are flowing, and the effort’s definitely going to be made,” the tech guru said. “So the big challenge now is to try to take all of this energy and make sure it goes to something positive, and we’re able to build something that has real near-term user value, because my worry is that we could spend years, and thousands of people, possibly, and wind up with things that didn’t contribute all that much to the ways that people are actually using the devices and hardware today.”

Carmack said next year’s Connect conference really ought to take place in the metaverse. “If we can’t handle this, we can’t handle the vision,” he said. “I’ll be really disappointed if I’m sitting here next year in front of a video crew and a camera in physical reality doing this talk. I want to be walking around the halls or walking around the stage as my avatar in front of thousands of people getting the feed across multiple platforms. I’m laying that gauntlet down right now.”

However, he noted, the technology isn’t there yet. In Facebook’s Horizon Workrooms app for Oculus—a virtual reality Zoom rival—having just 16 participants causes the system to stutter. “In Workrooms we can’t have our VR leads meeting because there’s too many people on the call,” he said.

Does the solution lie in the cloud, with superpowerful processors handling graphical demands from afar? “I’m very supportive of cloud rendering architectures but I have to pull back a little bit and say that well, there’s going to be a lot of cost there. That would cut off a lot of people who don’t have the bandwidth to have that high quality of a connection,” said Carmack, adding that “the economics of this get really bad.”

He didn’t stop there. “And then to be even more contrarian here, I have to say are we necessarily even aiming for all the right targets here with the social metaverse, where the feeling of co-presence is the big bet?” Carmack mused. “It’s completely understandable why a company like Facebook or Meta would make that play; it’s what the company is built on. But in truth a lot of the luxury items in reality are freedom from co-presence. It’s a private office, a private beach, a private plane. Sometimes these things are just…add people is not always a positive, especially for people that are a little more on the introverted side of things.”

Carmack also warned against “the metaverse” being under the control of one company. “The problem is that if you make a bad decision at the central level, nobody can fix it,” he said. “You can cut off entire swaths of possibility—things that might be super important. I just don’t believe one company ends up making all the right decisions for this.”

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