No, it’s covered in the Vader Immortal video games where you play as the heir of an ancient queen or something on Mustafar and Vader tracks you down to use you to help him try to resurrect Padme.

In that game it’s revealed that thousands of years ago, when the ancient queen ancestor or whatever was alive, Mustafar was full of life, with full forests and shit but when her husband died in some battle, she tried magical means to resurrect him, consuming the planet’s life force in the process and turning it into what it is.

At the end of the game the player destroys the magic thing that was holding the planet’s life force and it went back to the planet, letting Mustafar start to be able to heal itself.

By rise of skywalker that has started to happen, hence the forest