In fact, it is the Oceans that are the lungs of the world.
Yes, Europe ( all of it, not just western) has more forests then ever. But the fields used to be small, and divided by hedges, streams, stone walls, things like that. lots of wetlands/flood areas.
Today much of the forests are planted and a mono culture.
Also one type of biome seems to have vanished. Open fields for grazing. Lots of lowers, insects, birds.
Now either monoforest covered, or covered with brush. Less flowers, less bees, less butterflies.