I don't think it has as much to do about fluctuations in value as Bitcoin's track record, or more specifically, its lack thereof. People who have held coins for longer than a year know that Bitcoin can hold its value really well, and that chances are it's going to be even more valuable in the future.

The problem, I think, is that Bitcoin hasn't even existed for a decade yet. I can't blame more traditional people for thinking precious metals are a much better option for storage of value considering the fact that they've been playing that role for centuries. Generations of people have gone that road without encountering any problems. "Tried and tested" typically trump "new and innovative" in cases where you need to wait decades for a result.

Fluctuations themselves shouldn't be too bad at the end of the day, but I imagine they may cause some unnecessary anxiety, so I can also see where that sentiment is coming from.