Yacon was originally used as a gimmick to attract consumers to buy, but consumers are not stupid. You will see the effect if you eat it for a long time. People naturally know whether it is as fantastic as the merchants say.
Yacon is crisp and juicy, and the rest is just like eating sweet potatoes. It is tasteless and has no sweetness. There are so many delicious fruits in the market, people have more choices, so naturally they will not choose plain fruits to eat, so this is probably the reason why the market is so bleak now!