Can't upvote this enough. In Austin, with us on track to break the record of 100+ degree consecutive days, there is a huge difference between walking along nice, shaded areas and barren sidewalks. The trees don't even need to be that "mature" - I've seen new developments plant grown trees that only take a couple years to really expand.
Like the blog post and other commenters mentioned, it's not just trees alone but especially in hotter climates it can make all the difference.
It's crazy to me that people need to be reminded that trees, and plants in general, lower the temperature. Sufficient amounts of dense bushes do absolute wonders. I can feel the cool, moist air from 20 meters.
Animals understand this stuff just fine, yet certain modern humans somehow have trouble with the concept.
Near me there is a preserved section of forest (in the middle of a suburban sprawl). It connects a senior-living apartment building to a Walgreens, nothing more. It's one block wide and two blocks long, just enough forest for a winding walkway to never see the roads on either side.
When you step into the walkway you immediately feel the cool and moisture. It feels magical.
Like the blog post and other commenters mentioned, it's not just trees alone but especially in hotter climates it can make all the difference.