The absolute price doesn't matter. If the price declines a lot then the HBD is capped at 10%. This has happened before and the sky didn't fall. Even if the 10% is increased, it's still capped. It could go up to a trillion MC and if and when it declines, the dynamic is the same.

I understand your distinction between price and inflation but I don't agree that distinction is very important. Low inflation with a low or declining price is still a failure. High inflation with a high or rising price is okay. Both of these are entirely plausible to me. I don't think every blockchain project needs to copy Bitcoin's fixed supply model.