The Paris Agreement calls on us to limit global warming to 1.5 degrees Celsius above pre-industrial levels. To reach this goal, we need to reduce CO₂ emissions and remove existing CO₂ from the atmosphere.
Climate change requires every solution and then a couple more. There is no "less impactful than" with climate change mitigation/reversal. We need all of it and then some.
The problem is not with people focusing in reforestation. It's with corporations using the funding of reforestation to greenwash or "balance" their more harmful practices. The point is that they need to stop doing harm. After that, how they choose to do good is a secondary issue.