Too late for that, tether is popular because a lot of people are scared of volatility, a lot of so-called traders entered the market for quick gains but they are afraid to leave their funds in some coin and they quickly convert them to tether so they can sleep easily at night.
It might not have gained traction in RL shopping but it might and at that point..god knows what might happened next.
Unfortunately, the masses are all about $ and instinctively when they don't have a clue what will happen next they tend to switch their stash to something that would not lose value against the $ no matter how bad the news hitting the crypto world is. Quite interesting, a lot of people also predict the fall of the usd and euro but that isn't making them switching all the savings into crypto either, no matter how scared of a fall they are they still keep their funds in fiat. Because of convenience, because of...who knows.
In short, it's a bit too late for those coins to NOT gain popularity or even more popularity.