“Somewhere between my original vision for web 1.0 and the rise of social media as part of web 2.0, we took the wrong path,” Berners-Lee wrote in the Guardian.

He added: “I look at my invention and I am forced to ask: is the web still free today? No, not all of it. We see a handful of large platforms harvesting users’ private data to share with commercial brokers or even repressive governments. We see ubiquitous algorithms that are addictive by design and damaging to our teenagers’ mental health. Trading personal data for use certainly does not fit with my vision for a free web.”

Berners-Lee blasted the fact that people’s data is sold off, often anonymised, to shadowy actors who then sling ads and content back at them.

He argued that we already have the tech to fix this. Solid, the open-source standard he and his team at MIT built more than a decade ago, gives individuals direct control of their data.

“Apps running on Solid don’t implicitly own your data, they have to request it from you and you choose whether to agree, or not,” Berners-Lee explained.

He pointed out the absurdity of data being siloed everywhere. “Why is your smartwatch writing your biological data to one silo in one format? Why is your credit card writing your financial data to a second silo in a different format? Why are your YouTube comments, Reddit posts, Facebook updates and tweets all stored in different places?” he asked.

Berners-Lee said users should own and be empowered by the information they generate through daily actions, choices and preferences.

He warned that AI is another crossroads moment. Policymakers, he said, must not repeat their decade-long game of catch-up as they did with social media.

“The time to decide the governance model for AI was yesterday, so we must act with urgency,” he wrote.

In 2017, he floated the idea of Charlie, an AI assistant bound by the same codes of conduct and regulation as a doctor or lawyer. He now argues such frameworks should apply more broadly before monopolies grab control.

Berners-Lee wants to see a CERN-style not-for-profit body to steer international AI research, saying: “We have the chance to restore the web as a tool for collaboration, creativity and compassion across cultural borders. We can re-empower individuals, and take the web back. It’s not too late.”

He has also penned a new book, This is For Everyone, laying out his vision for reclaiming the internet from corporate overlords.