Imagine you are an archeologist in the year 2222, and you have come across an absolute treasure: A buried server farm containing all the YouTube videos of 2022. This should give you a brilliant opportunity to find out how people lived 200 years ago. Does it?
The first problem with that idea is that YouTube is obviously not geographically representative of the real world. The 40 million inhabitants of California produced a lot more YouTube videos in 2022 than the 1.4 billion inhabitants of Africa. To get an idea about China, you'd need to look a WeChat and Weibo, not YouTube. And even within the USA, YouTube demographics aren't representative: The average YouTuber is younger, whiter, more likely to be male, and richer than the average American.
The second problem with using YouTube to find out about the lives of real people is that the large majority of YouTube videos don't have the lives of real people as the subject. A huge number of YouTube videos are about fiction: Video games, movies, TV series, books, and so on. That would give an archeologist an idea what the entertainment in 2022 was about, but not much more.
The third, and probably most deceptive problem for the future archeologist is one that has plagued historians since the profession exists: Average people are boring, which is why they don't appear much in historical records. We know a lot more about the histories of kings and queens than we know about their subjects, in spite of there obviously being a lot more subjects than kings. YouTube has the same problem: It is easy to find videos about people driving Lamborghinis, although only 9,233 of these cars were sold in 2022. And you can probably find a lot of documentaries of people queuing up at food banks, or other cost-of-living crisis reporting. But good luck finding anything about a US household making around the median income of $70k per year. We know how the average person lives, because this is us, but we aren't leaving a lot of records about our lives, because even we think our lives are boring.
Now, the problems of future archeologists are probably not very important. But the lack of YouTube to show real lives of average people does have consequences today. All those videos with the Lambos have the driver get out of his car and try to sell you a get-rich-quick scheme or course. The glamorous lives of influencers cause depression and anxiety in the viewers, because it makes them think that they are doing a lot worse than they actually do. On the other side of the spectrum, people are making political capital by exaggerating the problems. This is the century in which people decided that they can't trust the press, so they instead turned to social media, which turns out to be significantly less trustworthy still. This is how we got into the post-truth society. Half of the people on social media deliberately lie, and the other half misrepresents because the misrepresentation gets more attention than the boring reality. The old motto of Google was "don't be evil", but I think they underestimated the evil that their search algorithms on the search engine, and the recommendation algorithms on YouTube would ultimately bring us.