As mentioned, the current interest rate is essentially meaningless relative to the current volatility (to traders who currently speculate on the rather meaningless of HBD once it goes much over $1 on the markets). But this change is being proposed in concert with the change that is planned to peg HBD. In other words, if the new operation to maintain the peg works correctly, there won't be many people speculating on the price of HBD any more and hence little risk of missing a speculative opportunity.

But if you're just arguing against staking rewards as a "good thing" in DeFi, I'm not the one to defend the concept. I just recognize it is a popular one in cryptocurrency now and a lot of Hive stakeholders would like to see similar functionality here in Hive.