The comments did not simply pile criticism on Kalanick or Uber, however. For many, the driver wasn't exactly blameless.
"I better Never have a driver treat me like that!" one poster remarked.
Others remarked that the way the driver spoke to Kalanick would be a fireable offense if it were any other passenger.
"If I did that to anyone off the street, I wouldn't be driving," someone offered.
To Twist, the driver was unprofessional but Kalanick should also have responded differently. "As the CEO and founder of such a large company, he is never really off duty," he said.
The video shows Kalanick riding in the back seat of an Uber black car with two companions. As he prepares to exit, the driver, Kamel, engages Kalanick in a conversation about the company's business model and the financial pressure that low-cost services put on drivers.
"We didn't go low-end because we wanted to," Kalanick tells Kamel. "We went low-end because we had to."
The conversation soon turns heated. When Kamel says that the company dropped the price of Uber's black car service, Kalanick points a finger and says "bullsh***."
When the driver says he has lost nearly $100,000 and tells Kalanick, "I'm bankrupt because of you," the chief executive fires back.
"You know what? Some people don't like to take responsibility for their own s***. They blame everything in their life on everyone else," Kalanick says.
Jessie Newburn of Columbia, Maryland, began driving for Uber more than a year ago and has documented the experience in books called "Uber Chronicles." Uber is running a business, not building a "family," she said, and drivers have to engage with the company accordingly.
That means having multiple streams of income, Newburn said. If you work in the"gig economy" - meaning you draw money from multiple small jobs - then you cannot rely on any single contract.
"A lot of people come to Uber with this sense of 'I'm going to make a lot of money.' It's not always as profitable as it may sound," Newburn said. "When people are upset, they throw their blames and criticisms all over the place."
But an Uber driver in Phoenix named Mark said his pay has taken a hit three times in the past year as Uber slashes fares. He declined to provide his last name out of concerns about retribution. The only fare hike in that time was 20 cents tacked onto the booking fee - a charge that Uber doesn't split with its drivers, he said.
"They just keep doing things that get under your skin," Mark said of Uber. "One little thing after another."
In January, Mark decided to give competitor Lyft a try and finds himself picking up more rides there. Lyft also runs more promotions and incentives for drivers, he said, making it easier to pull in bigger paychecks from time to time.
Twist, the Boston driver, also works for Lyft, but sparingly. It doesn't have the same name recognition as Uber, he said, and ultimately his income depends on rider demand.
"I feel like a bit of a sellout saying that . . . but at the end of it I need to make a living, too," he said.
The latest exchange is the third high-profile controversy for Uber since the start of the year. In January, the company was criticized for providing service to New York's JFK Airport despite a taxicab protest of President Donald Trump's immigration ban. That led to an Uber boycott and Kalanick's resignation from Trump's business council. Last month, a former employee publicly claimed that Uber failed to address her sexual harassment allegations, prompting the company to launch an internal review.