Shares of leading firms nose-dive after Nvidia’s Jensen Huang suggests a generational wait for fully functional quantum tech. We’ve been told that the future is now, but it seems it’s not quite here yet—at least not for quantum computing.

Rigetti Computing is at the forefront of the quantum computing industry, but the company has a speculative stock valuation.

The quantum computing rally came to an abrupt end on Wednesday following comments from Nvidia CEO Jensen Huang. During a question-and-answer session with analysts, Huang put forth a more pessimistic view of the quantum computing timeline:

Quantum computing companies have surged recently but Nvidia CEO Jensen Huang had a disappointing message for the sector.

The carnage in quantum computing stocks Wednesday saw shares of Rigetti Computing (NASDAQ:RGTI), Quantum Computing (NASDAQ:QUBT), and IonQ (NASDAQ:IONQ) plunge 40% or more. Comments made by Nvidia (NASDAQ:NVDA) CEO Jensen Huang that the sector won’t see viability for another two decades gutted these former high-flying stocks.

Wave fell sharply after Nvidia’s Jensen Huang said that “very simple quantum computers” could be 20 years away.

Quantum computing stocks sank on Wednesday, pausing a year-long rally, after Nvidia CEO Jensen Huang said the technology's practical use was likely two decades away. The long wait outlined by Huang for "very useful quantum computers" throws cold water on a sector that was already expected to spend millions more on the technology,

Steve Sosnick, Chief Strategist at Interactive Brokers (IBKR), spoke with Quartz for the latest installment of our “Smart Investing” video series.