Gently, respectfully, you have a point though it be shy of the mark.
In Middle Earth, the whole of Eä, The World That Is, has been marred to its roots by the meddling and corruption of Melkor before development en force by the workers of the Valar were sent to do their jobs to raise up the world into a thing that grows and thrives.
There is an ever-present spirit of malice that flows through the very bones of the world, that echos in the wood and rivers and the creatures, that wends and waits and whispers to the weakness in the folk to tempt them to cowardly evils.
The world is broken, almost before it began. The work to create all that was good had been foiled before it was begun. The world that did come to be was but a shadow of what it had been planned to be. The world cannot be other until it is Unmade and Remade by Eru Ilúvatar at the end of days, after the Last Battle.
That’s the thing. The world is corrupted, and the breaking of the grand seats of discordant and evil, selfish powers by the Good Folk who set themselves steadily against it for all of that place’s history, it wasn’t the final solution to evil and ills. That height of evil can and will still rise in the people who allow it in, though the fallen Vala will never rise again.
Tolkien stated it so himself.
There is no purging this spirit of evil from the earth until the Creator of it sees that it has come to the fullness of time, and called the Children that live there to safety, and then He unmakes and remakes the very essence of the world to that which He intended from the first.
The song must be played out first. It must unfold in the meter and time that it takes to let each note be.
Until then, the discord remains to corrupt the crooked hearts and minds. It cannot be purged by anything the Children can do. But that is not their burden. Their burden is to live as best the may in the meantime. To do what that can with the time that they are given.
The people after the Lord of the Rings had it easy.
The people in the Lord of the Rings teetered on the knife’s edge of every pre and First Age horror.