I think planting trees is always good, whether you're trying to say it's to reduce co2 or for shade, etc. The problem is when it's not properly planned. For example the trees should be planted in areas where they are expected to not be disturbed for decades. No point in planting them near road that might be widened a few years later.
Planting on side of the road is the best spot for trees to be planted, but how can you even know if an area will be widened few years later. It's like saying that there is no point in planting trees in an open lot when later on, subdivisions will be built in that area. Acting for the presents issue will be the best, we can move trees if they will widen the roads in the future.
It seems to me that if every person on the planet is attached to the fact that he planted at least 1 or 2 trees during his life, it would qualitatively be able to change life on the planet. We need to take care of more than one city, such as new York, we need to do it all over the world, because the Earth is our common home.
That was impossible to happen because we have a limited location to place in the future. It's surely cut again but that was good idea for atleast the number of trees would be grown.
In our university, it is part of our graduation requirement to at least plant 5 trees before the end of the final semester. And no student ever disapproved of this idea, every student actually agrees, and love this idea that they even take time to visit mountain areas that was subjected in illegal logging to be planted by trees who has no worth when cutted.