The agent provocateur took to Twitter claiming to have "enraged the idiocy of New Zealand".
"Christ, I've enraged the idiocy of New Zealand," MacKenna wrote on Twitter.
""Heritage". "Pride". "Warriors". "History". "Culture". Eh no, it's marketing and exploitation. Because if any of above nonsense wasn't via modern marketing campaign, this Haka wouldn't exist so recently."
In a column titled 'Haka gives New Zealand an unfair advantage and needs to stop' on sports website Pundit Arena, MacKenna asked why the World Cup is still "pandering to the dance".
"That's unfortunate as New Zealand are justifiably big-headed enough without a massaging of their already massive egos," MacKenna wrote.
"Yet even World Rugby have it in their rules that to not stand on your own 10-metre line and watch a bunch stick out their tongues and slap their thighs is worthy of a fine and a telling off.
"Indeed if we are to engage in these cultural activities in rugby, perhaps Ireland's opponents should have to spend a few minutes watching our players sitting around a table in midfield, sipping cups of tea and bemoaning everything from economic migrants to the latest bin charges."
MacKenna's tweet was received with expected backlash from Kiwis who urged him to educate himself on Māori culture.
"Hi Ewan, NZ idiot here," replied one user. "I think you need to educate yourself in Maori culture to truly understand the significance of the haka. In terms of the transition from the old haka, to the new - perhaps watch "By the Balls" a great NZ rugby doco that shares Buck Shelford's."
"How do you figure that?" asked another. "Have you ever been to a college schools game in nz and seen a Haka performed? You surely cant be that ignorant. Do you even know what the meaning of a tribe's haka is? To me it sounds more like jealousy and racism."
In the column, MacKenna said the haka had "been ruthlessly exploited and commercialised and ultimately cheapened".
"That's not to say it doesn't have beauty and meaning to Maoris [sic], but Irish dancing can having meaning to us and that doesn't change the fact that it was monetised by Michael Flatley turning to liquid plastic on stage."
After taking shots at the haka, MacKenna went on to attempt to describe the practical reasons why the traditional challenge gives New Zealand an advantage.
"There's a practical reason why the Haka shouldn't happen as, while it provides a psychological edge through self-inspiration and via an attempt at opponent intimidation, it also provides a small physical edge as others are forced to stand still and go briefly cold.
"There's another reason too though as there is a huge lack of self-awareness about this. Again there are those who'll say it's native and it is to some, but the majority of New Zealand players haven't been Maori. Instead, they descend from forefathers who were actually ruthless oppressors of natives.
"Anyway, it's completely overdone. In rugby, and in life. A New Zealand graduation or homecoming, a wedding afters or merely a boozed-up night out, it seems, can barely pass by without a YouTube video emerging of a man leaping about with all the authenticity of a Blackrock College conversation detailing both tillage methodology and livestock vaccination."
Tonga, Samoa and Fiji also perform traditional challenges before each test match.
This isn't the first time the haka has come under the microscope in world rugby, with similar questions being posed throughout All Black history.