It is true that TikTok has become a very popular social media format and now everyone is not only a photographer, but a videographer as well. This is just how social media platforms are, they can go from being very small and no one knows about them, to very popular where there are 1 billion downloads of it practically over night. And then it can become a thing of the past just as quickly. There are so many bigger and better things, so much information online that it is hard to keep track of.
I don’t think that other social media platforms will suffer too much. They will adapt every time there is something new that challenges it. Social media platforms that have a large community will be partially protected because of all of the following. This is why Twitter, Facebook and Instagram will still be around for many years to come. If they don’t, it is because they didn’t change with the times.