NFTs are very important for the future of Steem. Honestly, I think NFTs match more with the Steem concept than most blockchains because its another way to help musicians, artists, writers and other talent support themselves with rare collectible items.
Here is my question, and I'll go check it in more detail, but would it be possible to double spend the NFTs if we used soft-consensus?
I definitely agree with all your points in the first paragraph.
Actually no, it is not possible to double spend in a well constructed soft consensus. The Steem blockchain already orders transactions for us, like any blockchain, which means there is no conflict over which send transaction occured first.
If you have any more questions feel free to ask!