We shouldn't expect 10% to last "forever". Right now Hive is a speculative, ideally high growth, platform where 10% cost of capital is sustainable. Longer term if Hive is successful and large, I would expect rates similar to normal low-risk USD rates (currently 1% or less). But for now those who are here and aware of the opportunity and comfortable with the risks of a blockchain can take advantage of it.
RE: Savings interest rate at 10% APR and stable HBD: Hive as lucrative DeFi