"Yet trees can be reborn, and the act could lead to a greater legacy than the tree could have managed alone. Shortly after its destruction, the Sycamore Gap tree began to grow saplings around its stump"
The article ends on a hopeful note, and gives optimism for the future. For all the bad things humanity can do, humanity can also repent. When we realized that cutting down forests was bad for the environment, and when we realized our carbon emissions were causing climate change, we changed and took steps towards becoming more sustainable. So, one of the messages of the article is to remind readers that humans are two-sided. For all the evil we may have caused (cutting down the sycamore tree), it doesn't mean that we are all bad, and the outrage and the court trial against the people who cut down the tree is proof that there is still good in this world.