That's completely correct.
Also, hard to say that it entirely isn't working. HBD is definitely not stable, but it could be even less stable too. Also possible that it hasn't yet worked at past funding rates, but funding rates are increasing and it may at some point start working.
that's why I think a DAI version of it would work better :)
supply on demand.
IMO it would also increase the hive price, because for the demand on hive to generate the dai version + it would be locked up in that timeframe.
But for the moment, the proposal is the best thing we can do for now. But longterm ( midterm) we should think again about change it :)
And if it doesn't work, well, then it just works a different way.