[3] Plunket took over hosting the 9 am–noon weekday slot on Radio Live, later known as MagicTalk, from Michael Laws in April 2013,[13] continuing to December 2015, when he was replaced by Mark Sainsbury.

Plunket drew criticism for his remarks from Victoria University Press publisher Fergus Barrowman, TV3 journalist David Farrier, and arts commentator Hamish Keith, who defended Catton's right to freedom of expression and advocacy.

[17] In late September 2017, the Broadcasting Standards Authority appointed Plunket to a three-year term as a member of the media watchdog, commencing 1 October 2017.

[4] In September 2021, Plunket announced plans to start his own online talkback station called The Platform, which he said would promote free speech, democracy and debate.

[23] Besides Plunket, other notable hosts have included sports broadcaster Martin Devlin and Otago Regional Council member Michael Laws had joined the talkback station.

[27] As a host on The Platform, Plunket covered controversial anti-transgender activist[28] Kellie-Jay Keen-Minshull's ("Posie Parker") Auckland speaking event on 25 March 2023, which was disrupted by counter-protesters.

[29][30] On 3 April 2023, Plunket attracted media attention after asking Prime Minister Chris Hipkins during a press conference to define what was a woman.

This was part of a recent international trend of politicians including British Labour Party leader Keir Starmer and former Scottish First Minister Nicola Sturgeon being asked in media interviews to define womanhood.

Subsequently, Plunket removed references to the fake Ardern ad from his and The Platform’s social media and encouraged his followers to delete any mentions of it as well.

[5] In late October 2022, Plunket shared several screenshots on Twitter of a protection order filed against the investigative journalist and filmmaker David Farrier.

[35][36] On 22 December 2022, all charges against Farrier were dismissed by the New Zealand family court, which noted "significant embellishment in the initial affidavit" and "[t]here was not full and frank disclosure on this occasion.

In addition, human rights advocate Guled Mired confirmed that he had reported Plunket's Tweet encouraging people to read the Christchurch mosque shooter's manifesto, which is banned under New Zealand law, as "hateful content.

He credited Twitter owner Elon Musk, British broadcaster Piers Morgan, Canadian academic Jordan Peterson, Keen-Minshull, and Australian columnist Rita Panahi with reinstating his account.