“We’ve looked to the platforms themselves for answers. Companies are aware of the problems and are making efforts to fix them—with each change they make affecting millions of people. The responsibility—and sometimes burden—of making these decisions falls on companies that have been built to maximize profit more than to maximize social good. A legal or regulatory framework that accounts for social objectives may help ease those tensions,” he wrote in an open letter to mark the web’s 29th birthday.

Berners-Lee has sounded off about these issues before, though it’s unusual for him to call for more regulation on this front. In last year’s letter, the engineer urged Google and Facebook to fight against misinformation “while avoiding the creation of any central bodies to decide what is ‘true or not.'”

A lot has changed in the last year, with most people now accepting that Russia used the big online platforms to at least try to undermine the 2016 U.S. elections. An Axios-SurveyMonkey poll a couple weeks back suggested that the American public has in recent months—for the first time—switched on to the idea that regulating Big Tech might actually be a good thing.

The looming question now is how to deal with the issue without clashing with the First Amendment (though some argue it does not apply to the big platforms) and without encouraging online giants to take down information without proper scrutiny. Europe is trying to be ahead of the game when it comes to tackling “fake news,” but so far nobody there has come up with workable solutions, either.

It’s worth remembering that Berners-Lee is highlighting a deeper issue here, too. The root of the problem, he says, is that too much power has been concentrated in the hands of too few online corporations. Because “a handful of platforms…control which ideas and opinions are seen and shared,” he says, they’re ripe for co-opting.

Whatever the solutions to these platform problems might be, if they’re going to work, they may need to be more than merely cosmetic.