RE: What Is the Vision for HBD?

Are all these different purposes/functions mutually exclusive?

Perhaps HBD could fulfill a range of options? Certainly while we still have legacy systems.
There could be an apocalypse of one sort or another, I wouldn't rule it out, but until then, or as well as, I suspect that legacy systems are going to continue to linger on for a very long time. So to have a mechanism like HBD which is able to interact with different currencies is enormously helpful for all the different situations you set out.

I have started to save for a big expense I will have next year. For the first time since joining Hive (coming up to six years now) I have considered using HBD as a place to save for a real life expense, rather than somewhere I put surplus resources that are not needed for every day life. This is because I am reasonably confident that the value of HBD will be similar in 12 months to what it is now, and so I am able to take a considered risk in HBD.

At the end of that time, after I have withdrawn what I need, I will still have a nest egg (the accrued interest on my savings) which I can further use/invest as I wish - this is the way that credit unions work, at the end of paying off your debt, you're still better off than you were when you started. This would be why you would use HBD rather than fiat.

I've just used HBD to purchase some goods and their shipping from USA to UK through the Hive Thrifted community.

Another account set up an event in the UK (long ago) covering the costs with payments in Hive or HBD. By the time the event came around, neither token covered the fiat cost. Having some HBD stability would prevent one person taking all the risk and carrying all the liability and make it easier to organise.