The creator of HBO’s first one-hour original drama series criticized the premium network Saturday for not taking more programming risks in recent years.

Writer-producer Tom Fontana, who made NBC’s groundbreaking Homicide: Life on the Street, as well as HBO’s debut scripted drama, the dark prison series Oz, was on panel at the ATX Television Festival in Austin, Texas with fellow showrunner David Simon. The exchange about HBO began when Simon was discussing how the network supported his acclaimed struggling drama The Wire.

“I remember we got terrible numbers for season 3, and they never came back,” Simon said. “I remember calling [then HBO executive] Carolyn Strauss and saying, ‘Are we canceled?’ and she said, ‘Oh, it’s a cute little number. Don’t worry about numbers.’ And they could afford to be that way because we were being subsidized by The Sopranos — and I’m not saying that’s a bad thing. Sopranos was a brilliant show. But the backside was, after that, there was a lot of gaming the ball, ‘We can make another Sopranos,,’ and a lot less of: ‘Why are we telling the story? Has it never been on TV? Is the story worth telling? Go tell it.’ Those days are — I haven’t experienced that since.”

Fontana then added, “There’s a very bizarre phenomenon that happens in television, which probably happens everywhere: success breeds fear as much as failure does. And that’s what happened at HBO. They became afraid that they were’t going to find the next Sopranos and they could actually dictate what the next Sopranos was going to be. The other thing that happened is that HBO — which was owned by Time Warner — Time Warner merged with AOL in an ill-fated marriage. And like what also happened with a lot of broadcast networks, the corporate nature of the day-to-day life at HBO changed. [Former HBO chairman and CEO Chris Albrecht] could no longer sit in a room with two people and say, ‘Lets make it.’ He was no longer free to do that because there were too many corporate entities at stake now.”

At that point, Simon came back to partly defend the network, pointing to his recent miniseries Show Me a Hero, which tackled a neighborhood’s resistance to a federally mandated public housing development. “I don’t want to suggest there’s not really good work being done at HBO,” Simon said. “I got to make a piece last year on housing in Yonkers [about] housing policy and hyper-segregration … so [quality, unconventional programming is] still happening. It’s happening because Game of Thrones is subsidizing all of us. But it’s also happening because [Show Me a Hero is only] six hours. … They understand that’s not going to be the next Sopranos.”

Joked Fontana: “I told you to put a dragon in that show, but you wouldn’t listen.”

Thrones, of course, is not only HBO’s most popular series of all time, but also broke Emmy records in 2015 to become the most honored drama ever in a single year. And when Thrones launched, the program actually considered highly risky as nobody had ever made a successful adult fantasy drama on TV before.

Earlier in the conversation, Fontana told the origin story of the gritty prison drama Oz, which in some respects gave HBO a template for its success moving forward — making bold shows that couldn’t, or wouldn’t, be made anywhere else. “I had been pitching a show about prisons constantly,” he recalled. “You watch cop shows all your life and the bad guys go to prison and the cops [are happy]. And you’re like: ‘What happened to that guy who went to prison?’ You can imagine going to CBS and pitching this prison show.” Then Fontana struck a deal at HBO, which at the time had never produced a scripted original drama series. Albrecht, he said, greenlit the series immediately after watching a pilot presentation with the producers in his office, which at the time was considered a stunningly impulsive move. “Everybody in the business [told me]: ‘This is the stupidest move you’ve ever made, nobody watches HBO.’ And I was like: ‘They’re going to let me do anything I want.'”