There is no telling what percentage of those numbers are actually just bots and useless bought-and-sold accounts. There are already plenty of them and they will continue to increase.
With algorithms giving targeted advertisements and content to people, these social media companies are killing the very reason that they exist, as a platform for human interactions. They are becoming these soul-less stages with repetitive, addictive content that is a net negative in the lives of anyone who uses these platforms. As more and more people realize the harmful effects, their market will, hopefully, keep shrinking.
There are no easy solutions. What is clear is that these platform are doing a big disservice to humanity by zombifying our thought processes. If you are not inherently creative, it is really difficult to net get lost and waste hours of time and mind-share on watching all the stupidity circulating in the name of user generated content.