The only question is whether you can exchange the new "TetherGold" for real gold and how.
Well, that's certainly not the only question I'd have about it--but regardless, I don't think this is a good idea even if it's real. There has been talk about gold-backed crypto for years, as I remember seeing discussion about it from my early days on the forum. And from all the comments I've read, it doesn't seem like it would be particularly popular--not to mention the fact that you'd have to trust someone to actually have the gold that the crypto represents. That's a big problem, and there have been other gold-backed digital currencies before (they were more like securities) that turned out to be scams.
If you really want to own gold, just buy some physical gold. If you don't want to physically own it, there are ETFs and mining stocks and that sort of thing. I wouldn't want to own a cryptocurrency that's
supposedly backed by gold, since there would be too much doubt in my mind as to whether the gold exists in somebody's vault.