I think that only 10% coins/tokens that would be able to survive and will be worth investing in 2021.
It's a difficult possibility to predict in the future. Every year there are only good projects that are worked on, there are also old coin that rise in 2021. If it is predicted how many tokens will grow, the answer is all have the same opportunity, depending on the developers who innovate. Technology is always evolving. Whoever cannot keep up with the times will be left behind.