Sounds like a justification after the fact to me.Because druids are all about appreciating nature as it is and dwarves are all about improving nature through work. For a dwarf a mountain does not have inherent beauty but it has potential beauty after hard work has been done to perfect it. This is very much opposed to the druid ethic.
Some Dwarves might think that the mountain needs to be improved, but a Dwarven Druid certainly doesn't; he's all about stone the way it is!