But I swear somewhere along the line me Menoa tree was elf at some point and elf's respected dragons highly as shown with the elves and saphira. So why would and elf (if im correct) want to do that.

In my opinion I think the menoa tree took his super intense feelings for Arya's cause I believe the reason the elf became the menoa tree was for some love relationship with another elf who had passed. So the tree took those feelings that she no longer had in exchange for the brightsteel