"Modify the genomes of elephants like those, as nature modified their ancestors’ across hundreds of thousands of years, and you can make your own mammoths."

Yeah, right... They make it sound like putting together a child puzzle.

The differences between those 2 genomes can be vast and even if we did know it 100%, it would take a lot of effort to "craft" this DNA into a usable one and after that how would you have variance? You would need to craft at least a couple dozens randomly changing it so they can breed or would we clone the same one over and over again?

I think it's interesting to bring it back, I would even like to see it but it is one weird of a project to say the least.