Broadcasters can arrest their fall in ratings by making “really clever and difficult programs,” according to Dorothy Byrne, Channel 4’s head of news and current affairs, who delivered the keynote MacTaggart lecture at the Edinburgh TV Festival on Wednesday night.

Speaking to an Edinburgh auditorium packed with many of the U.K.’s most senior executives, Byrne said that broadcasters who are “desperate for young audiences” should tap into the fact that millions of them are now politically aware and active, listening to podcasts and TED Talks and reading books on serious subjects such as climate change and the viability of financial systems.

“We have to stop being afraid of serious analysis authored by big brainy people. We have the ability and we have the airtime. Let’s make some really clever and difficult programs.”

Byrne, who was following in the footsteps of previous MacTaggart lecturers such as Rupert Murdoch and Ted Turner, said there is a lack of big ideas on TV at a time when society is undergoing seismic changes. “So often I’m told that documentary formats now deal with important subject matters but formats only describe society as it is, they don’t provide a vision for change.”

“If we are worried about becoming irrelevant, one of the best things we can do is to start making big controversial programs about the U.K. which put us back at the heart of public debate as we used to be.”

She also said that U.K. broadcasters should think about what makes them stand out against international streaming rivals such as Netflix. “We are the only people who have any interest in saying big things about Britain. That’s not the role of Netflix or other streaming services, terrific as they are in many ways.”

Byrne, a highly regarded news and current affairs executive who has worked at Channel 4 for 20 years, said she counted 29 different programs on Netflix about drugs, and a plethora of programs about serial killers. “I wonder if there’s a drug cartel anywhere that’s not currently being followed by a streaming service,” she said.

She also talked at length about the dramatic fall in the number of politicians holding themselves up to proper scrutiny on TV, saying that the decline has become “critical for our democracy.”

“British Prime Minister Boris Johnson hasn’t held one major press conference or given a major television interview since he came to power in July,” said Byrne. She added that the leader of the opposition Labour Party in the U.K., Jeremy Corbyn, similarly fails to give significant interviews on terrestrial TV.

“I genuinely fear that in the next election campaign there will be too little proper democratic debate and scrutiny to enable voters to make informed decisions.”

She said this echoed the policy of President Trump, who “has abandoned formal White House briefings. He, like our PM, prefers to take questions from journalists during photo opps, notably getting onto his helicopter…Journalists have to shout out and there is no opportunity for follow-ups.”

She compared this to the past when leaders such as Prime Minister Margaret Thatcher subjected themselves to half hour or 45 minute interviews on television.

“In the difficult period we are entering, we need the truth and we need proper scrutiny of all our major politicians. Television is a bulwark of our democracy, those who undermine its role are undermining democracy.

“It’s time for the television industry to stand up for itself and speak out publicly against what is happening. Yes, we are rivals but we have to form a united front in opposing attempts to side line our central role in the political life of this country.”

In a wide ranging and hard-hitting MacTaggart, Byrne also addressed the sexism she faced when starting out in her career, which included working as the only woman on legendary U.K. investigative current affairs show “World in Action,” which was made by Granada for ITV. She said that she was sexually assaulted by a director on her first day working at Granada.

She also said that the lack of progress in increasing ethnic diversity is the single most disappointing failure during her nearly 40-year career in TV.