Yeah, but ecological damage isn't about CO2. It's about global ecosystem collapse. Reforestation helps stopping damage to local wildlife, keep bees alive, etc. If we focus only on CO2 we run the risk of falling into technocratic strategies of minimaxing it's mitigation. All that while ignoring what we are trying to preserve in the first place.

Trees also help lowering local temperature, and a small but significant part of that carbon will be absorbed by fungi and stored bellow the Earth. And with diversity, they can provide resources for communities such as fruits, teas, and other good stuff.