Don't you care how well provided for your grandchildren will be when you are gone? Our grandchildren will still be around to use bitcoin when we are long gone and dead, and if we leave a mess behind, they inherit it.
Sure, but this isn't a question about whether a mess is being left behind. This is a question about trying to guess what the exchange rate volatility will be more than 120 years from now on a deflationary currency. Any answer is no more than a silly guess. There's no way to know how (or if) future generations will value bitcoin or if they'll even continue to value bitcoin at all.
Here's a similarly silly question...
Will the exchange rate of gold be more volitile or less volitile between the years 2130 and 2150 than it was between the years 2005 and 2015?
If you can't answer this question with certainty, then are you concerned that gold might be leaving a mess behind for future generations to inherit? How do you intend to fix this gold problem?