The internet was sent into meltdown this weekend after YouTube star KSI announced he was leaving Sidemen after more than 13 years.
In an emotional video titled "I'm leaving the Sidemen", KSI told fans that he would no longer be appearing in Sidemen content, describing the decision as one of the hardest he has ever made. Almost immediately, social media exploded with reactions, theories and speculation.
But alongside the shock came a different question: Is it actually real?
With TikTok, Instagram, YouTube and X flooded with theories claiming the announcement is fake, it's become a perfect example of how quickly rumours can spread online.
Who is KSI?
KSI, whose real name is Olajide Olatunji, is one of the UK's biggest online creators. Starting out by uploading FIFA gaming videos to YouTube, he has since become a musician, boxer, entrepreneur and television personality.
He is also one of the founding members of the Sidemen collective, a British YouTube collective formed in 2013 alongside creators including Simon Minter (Miniminter), Josh Bradley (Zerkaa), Tobi Brown (TBJZL), Ethan Payne (Behzinga), Vikram Barn (Vikkstar123) and Harry Lewis (W2S). Together, the group has built one of the biggest entertainment brands on the internet.
Is KSI really leaving Sidemen?
According to multiple news outlets and statements from representatives, the answer appears to be yes.
In his video, KSI explained he had spent months thinking about the decision and wanted to focus more on his personal life, health and work-life balance. Reports from several major media organisations have since stated that representatives confirmed the announcement was genuine.
Sidemen also released a statement acknowledging his departure, adding further weight to the announcement.
However, that hasn't stopped fans from questioning whether there's more to the story.
The internet's biggest theories
As soon as the video dropped, social media filled with reaction videos attempting to work out whether the announcement was genuine.
YouTuber Brandon Conner posted a video discussing several popular fan theories. Some viewers suggested KSI's departure could somehow be linked to Arsenal, his favourite football club failing to win the Champions League. Others claimed he appeared to be reading from a script off-camera, leading some to speculate he was being told what to say.
Another theory points to history. In 2017, KSI appeared to leave Sidemen during a highly publicised fallout that later turned out to be partly staged entertainment content. Because of that previous incident, some fans believe this latest announcement could be another publicity stunt.
Popular streamer Jynxzi also shared his reaction, initially suggesting he thought the announcement might not be real. He later posted another video claiming he had spoken to KSI's younger brother, Deji, who reportedly confirmed the news was genuine.
Other creators, including ArthurTV Live and numerous TikTok commentators, have also weighed in, with some convinced it's real and others certain there is a hidden twist still to come.
Why people are so quick to believe theories
The KSI situation highlights something increasingly common online: when a major story breaks, speculation often spreads faster than facts.
Social media platforms reward engagement. A dramatic theory, shocking claim or emotional reaction is more likely to get likes, shares and comments than a simple statement saying, "We'll have to wait for more information."
As a result, rumours can travel across TikTok, Instagram and YouTube before anyone has verified whether they're true. Just because a video has millions of views doesn't mean the information in it is accurate.
How to know if a story is fake
Stories like this provide an important reminder to think critically before sharing information online.
Check multiple reliable sources
If a claim only appears on one TikTok account or one YouTube channel, be cautious. Look to see whether established news organisations, official statements or the people involved have confirmed the information themselves.
In KSI's case, multiple media outlets reported that representatives confirmed the announcement was genuine.
Check the original source
Rather than relying on clips reposted by other accounts, find the original video, statement or interview. Watching KSI's full announcement gives much more context than seeing a ten-second clip on TikTok.
Be careful with old information
One reason some fans doubted the announcement is because of KSI's previous Sidemen exit storyline in 2017. However, just because something happened before doesn't mean the same thing is happening again.
Always check whether comparisons being made online are actually relevant.
Look for confirmation and not just agreement
Social media algorithms often show us content that reinforces what we already believe. If you think KSI's announcement is fake, you'll probably be shown more videos claiming it's fake.
Try actively seeking out evidence from different viewpoints rather than only consuming content that agrees with your opinion.
Think Before You Share
One of the easiest ways misinformation spreads is through well-meaning people reposting content without checking it first.
Before sharing a claim, ask yourself: "Do I actually know this is true?". If the answer is no, it may be worth waiting for more information.
Multiple reports and statements suggest KSI's departure from Sidemen is genuine. Whether fans fully believe it or not, the reaction shows just how difficult it can be to separate fact from speculation in today's online world.
This article was published in May 2026
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