In a “fireside chat” with U.S. Commerce Secretary Howard Lutnick, Altman called AI “incredible magic of intelligence in a bottle,” while also warning AI’s infrastructure needs would keep expanding.

“Even with great gains in efficiency, we are going to need to build much more infrastructure, unless we want this to be a highly priced model, which we don’t,” he added, according to local news outlet the News & Observer.

Nvidia CEO Jensen Huang and Palantir CEO Alex Karp were also present and projected similar positive messages. Tesla CEO Elon Musk spoke via conference call.

Beyond the security perimeter just outside the Carolina Inn, a hotel on the campus of the University of North Carolina where the tech leaders gathered, hundreds of protestors assembled on Wednesday morning to voice their displeasure with AI, data centers, and the billionaires behind them, among other concerns. 

“We are mad because AI data centers are polluting the water and the air in many communities,” said Rob, a college student who wished to be identified only by his first name. 

Others, like Melisande Timblin, a 2005 graduate of the university, called out what she said were false promises of long-term employment touted by data center developers.

“They come in and they sell them a big lie. They say we’re going to build these data centers. It’s going to provide hundreds of jobs building this data center. Okay, you’re going to give these people jobs for just a few years while you build it,” Timblin told Fortune. 

The contrast inside and outside the G20 this week highlights the growing reputational problem AI is facing as data centers crop up nationwide amid growing protests.

Altman and Anthropic CEO Dario Amodei have both softened their earlier dire warnings about AI job displacement, some of which have fed the tech’s unpopularity. Amodei once made waves by saying AI could replace 50% of white collar jobs, but more recently has called AI a multiplier of jobs. Altman, for his part, said this year AI is unlikely to lead to a “jobs apocalypse.”

Still, Amodei also acknowledged last month that AI faced a crisis of trust among the general public and said it must produce a breakthrough, like curing cancer, to earn it back.

Partly because they’re the most visible manifestation of AI, data centers have become the focus of protests nationwide. Residents across the country have pushed back against projects over concerns about data centers’ demand for electricity and water, as well as the potential for pollution.

Activists staged 142 demonstrations against data centers across 42 states in July alone, Reuters reported. And public opinion is strongly on their side. A poll from the Economist and YouGov earlier this week found that two-thirds of Americans are opposed to building a data center in their local area.

Nationwide, data centers have emerged as a major midterm election issue on both sides of the aisle. Even in Texas, the state with the second most data centers in the country, Republican Gov. Greg Abbot recently introduced stricter rules for data centers amid a close re-election race. Republican Attorney General Ken Paxton, who is facing a tight contest for a Senate seat, also hardened his stance against data centers recently. 

In North Carolina, where the G20 meeting in Chapel Hill took place, dozens of local governments have adopted moratoriums or tighter zoning rules as data center proposals spread across the state.

At the same time, more than 3,000 data centers are planned or are under construction, adding to the approximately 4,000 that exist already, according to the Associated Press.

Executives argue that to bring more capable AI to more people requires additional infrastructure development, which also driving demand for construction jobs and related services. Manufacturers of construction equipment are also booming. Signs of mass AI job displacement have yet to materialize.

And in places like Virginia’s Loudoun County, which has the highest concentration of data centers in the world, officials have been able to lower residential property tax rates every year over the past decade because they have been offset by income from data centers in the area.

In fact, not everyone outside the Carolina Inn Wednesday was opposed to AI itself. John Montavon, a local resident and former teacher, said he was not anti-technology and said it could be used in both “positive and negative ways.” 

Still, he questioned whether the people inside should be entrusted with determining how it develops.

“I’m concerned about the future of our communities,” Montavon told Fortune.