You will definitely find a lot of coins professed to be backed by so many assets, which mainly could be digital, but I still prefer those backed by real physical assets. Gold is a real asset and there are some backed by real estates. Backing a coin by an already established coin, might sometimes not be substantial enough, because anything can happen along the line.
Show me at least one project that has a coin backed by gold? Even if there is information about it on the project website, it does not mean that it is.
Tell me about the process of investigating how a coin is backed by gold and I would do it. See? The problem is that we don't get enough transparency
for so "backed" coins. However I don't think backed coins are bad, fake backed coins however they are! (unless they are constantly fake backed so it looks like they are realistically backed)