I live in Japan so I have some experience. There are almost zero trees in all of the hottest places where the majority of people dwell. There are basically three decent sized parks with trees in the entire Tokyo metro area, which is tens of millions of peoples home. Literally the only way to survive most summers is hopping from air con to air con. I couldn't really stand it so I left.

Pus, they cut down large trees (or trim them to a stump) en masse... because of an invasive beetle or fungus? No. Because the leaves are annoying to clean up in the fall. Because the branches are "unsightly." Because it's make-work. Who knows? I see more and more shade-giving trees get stumpified every year.

And Japan's history of planting trees is... mediocre at best. They planted a lot, but pure (now not only useless {no lumber value} but harmful due to pollen fever) monoculture.