Mr Turnbull told Sky News on Friday that the reforms were necessary to bridge the divide between Australian media and international companies including Facebook and Google.
“We’ve got to give Aussie media companies a fair go, (and) the chance to compete,” he said.
“(They previous laws) were drafted and enacted in an age before the internet and really relate to a completely… an era before the smartphone, before Facebook, before Google. It was another world.”
Mr Turnbull said his government had managed to bring Australian media laws into the 21st century.
The man who helped the Turnbull government secure its long-awaited media reforms concedes the changes will lead to less ownership diversity.
Crossbench senator Nick Xenophon says some mergers could save some regional broadcasters whose revenue and share price have plummeted.
"I do not want to see more media companies, large and small, go into administration or worse receivership and shed hundreds more journalists jobs," he told ABC radio.
Communications Minister Mitch Fifield said it was up to media proprietors to decide how they configure themselves, but the reforms put the industry on a more viable footing.
"We've given them the opportunity to have a wider range of dance partners," he said, insisting there were still diversity protections.
Senator Xenophon's critical bloc of three votes got the minister's package over the line in the Senate on Thursday night.
In exchange for his support to repeal rules governing who can own what, he secured a $60.4 million fund for regional and small publishers with a turnover of less than $30 million as well as cadetships and regional scholarships.
That was in addition to an Australian Competition and Consumer Commission inquiry into Facebook, Google and the impact other internet giants are having on the media industry.
The senator admitted the innovation fund could be accessed by the likes of Crikey and The Saturday Paper.
The coalition separately clinched a deal with One Nation, with separate legislation to be introduced to include the words 'fair' and 'balanced' into the ABC Act and more transparency over ABC and SBS pay.
But Senator Xenophon said a slated inquiry into the 'competitive neutrality' of the ABC, which Greens leader Richard Di Natale fears could leads to pay walls on services such as iView, would be "political suicide".
"That is something that would be simply unacceptable," he said.
"Australians will find that repugnant."
