But among the predictably angry tweets, one response was different, suggesting Thomas was not in a position to lecture anyone on racial insensitivities.
Activist, actor and writer Moreblessing Maturure posted a YouTube link to a 2016 panel discussion on writer's rooms Thomas had participated in alongside fellow writer/actors Dan Harmon, Celia Pacquola and Luke McGregor, and hosted by Gretel Killeen.
Maturure claimed Thomas' comments during the panel discussion had since become "infamous" among those in the industry – the lesson? "Don't be The Josh of the room."
WHAT JOSH SAID
The clip in question sees Thomas, who was the creator, writer, star and occasional director of his cult hit series Please Like Me, discussing difficulties in casting actors from diverse backgrounds.
Warning that "this is going to sound racist," Thomas said, "most of the immigrants in Australia have come pretty recently, and generally, first or second-generation immigrants don't want to be actors. They have real jobs.
"The other thing I didn't know about making a TV show that I found quite confronting is you have to pick every person. 'Josh, what do you want the 7-11 worker to look like?' Do you make them Indian, or is that offensive? Or if you make them white, is it a bit like you're lying, really? What do you do?"
"But also, it's taking a job away from an Indian actor if you don't," Pacquola said.
"What answer is not offensive?" Thomas pondered, prompting an interjection from McGregor acknowledging the all-white panel: "We're probably not going to come to the answer with this panel."
Community and Rick And Morty creator Harmon then spoke about efforts in Hollywood to make TV writers rooms more diverse, before Thomas interrupted.
"I feel like I just tried to say this and they thought it was racist, so I love that you're doubling down on it … Finding people who have been given the same opportunities to be great at acting is really hard. None of the other shows are hiring people that aren't white.
"Finding an experienced actor that's not white is really hard. You find yourself in a situation where you want to be more diverse, but this person doesn't have as much experience as this person, and then it's hard to know what to do, because you don't want to be favouring people when they're not going to do a good job."
"In the states, the answer is you have to look harder," Harmon said.
'IT WAS A TOTAL S**T SHOW'
As the clip circulated on social media, actor Johnny Lahoud, who has appeared in TV shows including Underbelly and Here Come The Habibs, revealed he'd been in attendance at the session.
"I posted this to my Facebook back in 2016, walking out of the opera house after listening to Josh Thomas disrespect me and every other POC actor in Australia," he said.
"The hardest part of what I'm about to write is that I might jeopardise my career or be seen as a whiner," he had written in a Facebook status update posted on the evening of the panel, December 18, 2016.
"I love what I do but I feel trapped and imprisoned in an industry that has such a hard time acknowledging my existence. We are not guests in this country. We are f***ing Australian and it's about time the film and TV industry accepted that fact."
Lahoud wrote that after "having the displeasure of hearing Josh Thomas tell the audience why his show is so white," he had yelled from the audience for Thomas "to go f**k himself".
"So basically as non anglo saxon actors we don't exist BUT when we do exist we are only good for minor stereotyped roles. F**K YOU!"
"Dude I can absolutely confirm this. I saw it live, it was a total sh*t show even then!" replied comedian and Uptopia actor Nina Oyama, who suggested the festival needed to take some responsibility for booking an all-white panel to discuss diversity.
"When they first brought up diverse voices everyone looked at Celia (cos she was the only woman)," she recalled. "Sadly I feel like what Josh was saying really echoes the approach to casting in Australia today."
'I'M SUPER ASHAMED'
Facing a barrage of criticisms, Thomas issued an apology overnight, saying he was "super ashamed" of his comments in the clip.
"There is a clip circulating on Twitter of me on a panel a few years ago talking about diversity casting, and in it I am being a really dumb, illogical, insensitive idiot and it's gross. I am super ashamed of the comments I made, and would like to apologise," he wrote.
"Authentic diversity in casting (and behind the scenes) is something that is really important to me, and that has been important to me for a long time.
"The conversation about why the casting process in Australia is structured to keep out people who aren't white and straight, with symmetrical faces and no body fat percentage – is an important one to have, but the answers I offered in this clip are in no way constructive or correct.
"I am committed to doing better," he finished.