I don't know a single one of the YouTubers being mentioned here.

James Somerton.

Basically got massively called out by Hbomberguy for plagiarism on every single video and I am pretty sure James just nuked the account and restarted his grift under an alt.

Illuminaughtii was pretty wild.

JonTron said all that Great Replacement Theory racist shit but collab'd with Internet Historian on his B channel some time after. Haven't followed him in a long time so I donno if his career suffered.

Onision is nuts in so many dark and strange ways that were completely predictable.

Among them all I'm so glad that Internet Comment Etiquette has always been my favorite. Eric is a good boy.

Edit: Erik with a K is a good boy.

Onision had a pretty spectacular implosion, but he was always a pretty wild and controversial figure. Shane Dawson was another pretty massive one. Miranda Sings was also huge, then all the weird and creepy chats and stage moments came out, sank her whole brand.

Boogie2988

The Completionist. Socials went private and any videos finished but unreleased had the artwork changed so it wasn't obviously from the channel.

Some others that came to mind is ProJared with the sexts, but he eventually defended his side and continues to post new videos, and the controversy from the Nostalgia Critic group during the ChangeTheChannel campaign

Not a vlogger, but CarlH was a respected reddit user who had a long and successful series of C programming lessons on youtube. I remember going through some of his videos back in the day.

He was arrested for abusing and exploiting his own son for child pornography, and later commited suicide in jail. I guess you can't fall much harder.

One of the many reddit posts about the story: https://www.reddit.com/r/UnresolvedMysteries/comments/upkjb7/carl_h_once_made_a_following_for_himself_online/

It's pretty niche, but Mike Israetel of Renaissance Periodization is one of the biggest fitness youtubers who for years has thrown his phd around to become an authority on sports science. A critical review of his joke of a phd thesis was recently published and now it's pure chaos in this sphere

Probably pewdiepie. He was very popular before the incident, after which noone wanted to touch him. His Scare Pewdiepie show also got canceled. He has regained popularity again though.

SkyDoesMinecraft was pretty bad, and it just kept. Getting. Worse.

Pirate software

Not really "a" youtuber, but i thoroughly enjoyed watching roosterteeth crash and burn. I loved their goofy shit maybe 10 or 15 years ago, but goddamn the fame really went to their heads fast. Ray and Mikey and Jack were all mostly cool, but Geoff had this really toxic "failed jock" vibe that really put down everyone else for very little reason. Then you had straight up toxic narcissists join up over the years, then Ryan shitting the bed by trying to hook up with (possibly underage) fans. It all came crashing down hard. It started out as a fun group of gamers and quickly turned into this weird hazing/bullying/im more famous than you circlejerk.

Probably not the "biggest", but remember Gus Johnson? Looked like a promising up-and-comer in the Internet comedy space, and then he got cancelled and effectively disappeared over night.

Charlie Kirk?

Recently? Either Iilluminaughtii or Karl Jobst.

It's a tie between EDP445 and Onision.

Honorable mention goes to Illuminaughtii.

I don't really keep up, but is that Dr. Disrespect guy still considered a pedo pariah?

Laci green used to be a women's health feminist youtuber. Made a video titled "i took the red pill" and immediately lost 90% of her views followed by the channel dying within 10 videos.

Toby Turner was pretty big in my eyes, but then there was some controversy of abuse or minors or something, I can't remember. But he made me laugh so hard like not many YouTubers could, dude. His gameplay of that game with the dad on his bike with his kid in the back of the bike, my god. Those were the days.

i mean colleen ballinger/miranda sings

Illuminaughti and Iskall85

Braille Skateboarding used to be so cool. They even made it to the news in Australia with the first glass skateboard video.

Last I heard was the park was destroyed WITHOUT telling the rest of crew it was happening, so they all missed out on a final session.

Oof, for me in my world, there have been so many unfortunately.

John Kuckian, Jaclyn Hill, Jeffree Star, and more recently Raw Beauty Kristi though she's been in decline for a while.

Makeup Youtubers are something fucking else.

Chucke2008

I think was the channel name. He showed welding and fabrication, one day he was reading something weird on video Idk and got canceled.

There was a van life de-influencer called Dave2D (not the computer one) who lived in a van and demonstrated the harsh realities of living full time in a van, while also mocking and exposing van life influencers who made it look glamorous, and called out those who were obviously just living in a house and pretending to be living in vans for the insta. He regularly made fun of those vanlife couples, especially when they inevitably broke up, until a very famous recently single vanfluencer killed herself after enduring lots of harrassment by his followers, and then Dave2Ddeleted almost all his videos.

Then he moved into a car with a puppy in LA and someone stole his catalytic converter while he was sleeping in the car, then he moved to a tiny cabin in Montana and transitioned to painting on Livestream, and now as far as I know he has no presence on YouTube.

what ever happened to chills?

Not really a YouTuber but I've always been curious what happened about a decade ago with Chris Ziegler from The Verge, who was an editor but then accepted a job at Apple on the side, and was then fired by both companies. He then disappeared entirely from the record and everyone got real quiet about it.

Probably Albert Dyrlund

Jenna marbles was cool and then some asshole canceled her and now she's gone how about that fuck you all