A drop in the bucket, no, a drop in the ocean. It's no good to plant trees, for a good start you need to plan forests. And you can't plant a forest by sticking a bunch of saplings in the ground and then walking away... you have to construct a whole ecosystem, with enough diversity to create stability, otherwise you're at best slightly increasing the buffer size of the anual carbon cycle, not reducing long term carbon. That's why "global greening" didn't have any measurable impact on global warming.
Best estimates for how many trees it would take to start making a significant dent in atmospheric carbon is on the order of a trillion, btw. There are currently about 2-3 trillion on the planet. A few thousand years ago there were probably about 6 trillion.
Then we just need to allocate some land to plant one trillion of trees and let them in peace and the problem will be solved in 80 years. Or maybe two trillions and will be solved in 40 years... The sooner we start to do it and respect the plants as more than just goat food, the best chance to survive as society in the near future.
Why is this so difficult to understand? Maybe because many "lets plant trees" projects are just logging companies in disguise. Maybe because many people still expect low-effort magical solutions, and charity and free children work for environmental projects. Allocating just the minimum resources possible into building a future to reach the "feel good" point, is stupid. This is not entertainment, is the future of humans.
We need to plant more trees, period. Now. And we need to protect the precious trees that we have. We will need to think about replacing all the trees killed in the Ukraine genocide, for example, not only the buildings. And we will need to start punishing arsonists and "captain chainsaw" wannabee tools. Allowing arsonists or overgrazing just because their grandpas did it, will lead us to a mad max scenery with much better killing machines.
Best estimates for how many trees it would take to start making a significant dent in atmospheric carbon is on the order of a trillion, btw. There are currently about 2-3 trillion on the planet. A few thousand years ago there were probably about 6 trillion.