I'm not really sure on your definition of "authenticity" but it seems to me that TikTok users are optimising for the algorithm, for engagement and for advertising revenue just like on every other platform. If anything, TikTok seems to give users the power to be even more annoying and repetitive, between the computer-generated voiceovers and the same few songs being used over and over again ("oh no, oh no, oh no no no no no").

If you watch any food videos you’ll see the advertising soon enough though, usually in the form of rage bait or similar. Like using fast food as ingredients to recipes or way too much Velveeta in their recipe.