The biggest star on YouTube — by a long shot— is Felix "PewDiePie" Kjellberg.

This is Felix "PewDiePie" Kjellberg, but you already knew that, right?

He's a handsome Swedish guy who's best known for producing, editing, and starring in videos that focus on video games.

He's got over 50 million subscribers and his videos routinely enjoy millions (if not tens of millions) of views.

His top video by views, "A Funny Montage," has nearly 80 million views.

Sometimes he rants about stuff he's passionate about — whether that's YouTube culture or the media's representation of him or something else — but he's notorious for creating "Let's Play" videos of various video games.

He's also notorious for poking the hornet's nest every now and again. And that final quality has led to some problems for Kjellberg's lucrative career in video production.

For instance: After a recent spat with The Wall Street Journal in which Kjellberg was accused of creating racist content, YouTube-owned Maker Studios got cold feet about its relationship with him and cut ties.

Kjellberg's show "Scare PewDiePie" for YouTube Red, the company's premium streaming service, was canceled.

YouTube also broke ties with Kjellberg financially, cutting him out of the crucial "preferred advertising program" (which affords higher revenue shares to YouTube's biggest video producers).

This was how Kjellberg responded to a Wall Street Journal report claiming Kjellberg made several racist videos.

Much of his provocation stems from the open nature of YouTube.

Unlike television, YouTube is an open service where you can post (pretty much) whatever you want. This open culture, combined with Kjellberg's outsized comparative audience, puts him in a unique position: He's got a massive, loyal following that YouTube can't ignore.

So when YouTube advertisers pulled their ad dollars from the service recently — once again, after a Wall Street Journal report, where it was revealed that YouTube was serving ads on overtly racist and offensive content (not anything from Kjellberg) — Kjellberg took to his studio and addressed the problem:

"The reason why people love YouTube is because it's free, and it's open, and you can say whatever you want. It's not like television, where everything is behind executive producers and people saying, 'No you can't say that! Because then we'll do this!' It seems like YouTube is forced to turn into television at this point. That's gonna be bad for everyone. You want YouTube to continue being a free platform. I want YouTube to continue being a free platform. I understand that advertisers need to feel like they're spending money and it doesn't show up on racist videos. I understand that 100%. That's a terrible thing. But the whole thing is just so massively overblown."

To be clear, Kjellberg isn't excusing the racist content; he's pointing out the strong reaction advertisers are having to a handful of racist videos among the billions of YouTube videos online.

Because those advertisers pulled out of YouTube entirely, anyone making a living off ads on YouTube is no longer making money. More specifically — because YouTube does a poor job of policing offensive content — anyone making videos that aren't so nakedly offensive (like Kjellberg) is losing out on money from advertisers pulling their ads from the whole service.

And because of that — combined with some other recent changes YouTube made to its ad policy — Kjellberg says YouTube is "over." He's serious enough about it that his new show, called "Best Club," is being streamed on Twitch.

"Best Club" is being streamed on Twitch.

Kjellberg isn't shutting down his "PewDiePie" YouTube channel.

He points out in his latest video (titled "YOUTUBEISOVERPARTY") that he was planning on streaming more stuff regardless. Then again, YouTube has its own live video-streaming service.

That Kjellberg chose Twitch, an Amazon-owned competitor to YouTube, says a lot by itself.

Is YouTube — the outrageously popular online video service — "over"? Probably not.

Even without Kjellberg, hundreds of millions of people use YouTube to watch videos of all types. But it may be "over" in a cultural sense, as the service attempts a pivot toward paid TV offerings. As that shift continues, expect to see more of YouTube's homemade personalities either move to other services or adapt toward more produced, advertiser-friendly content.