Most of the worlds large forests are no more, many European countries are stripped of their old forests, so replanting those are required anyway, for other environmental concerns. They could on a permanent basis capture some percentage of the CO2. It is permanent if you view it as a forest and not individual tree.
I think that's basically correct on the scale that's needed. I don't even think turning trees into building materials is enough.
Planting a lot of trees and letting forests grow has the advantage that it's obviously possible with current tech, while the forest is expanding in mass that CO2 is being scrubbed, and it's conspicuously visible to people (garnering feelings of goodwill and participation), but I don't believe the relatively small amount of incremental forest that we could reasonably create will make a meaningful change on a 100-year basis.
There are other reasons to plant trees (well, plant plants in general), notably around rehabilitating land that is on the verge of desertification or the like.