People are worried because of the laws of supply and demand.
If you have something in short supply (in this case HBD), which is very desirable (because of the 20% interest rate), the price goes up.
Suppose the Federal Reserve offered 20% on dollar deposits - the interest rate combined with the strength of the US govt would mean that money flooded in and the dollar would strengthen relative to other currencies.
These laws of supply and demand mean HBD should be strengthening against bitcoin and the USD.
But it's not supposed to. The peg is incompatible with 20% interest rates. For 1 HBD to equal 1 USD while offering 20% interest requires massive selling of Hive relative to HBD.
There are three outcomes:
The peg is abandoned
The 20% interest rate is abandoned to reduce demand for HBD
You keep the 20% interest rate and Hive is sold and it's price driven down to maintain the peg.
RE: HBD 20% Interest Is Sustainable