This is very correct. Bitcoin acceptance is a product of its Volatility and would drop in any event of continuous stability. Bitcoin is an asset and not just a currency, so you can't expect it to be stable. If one needs a stable currency, let him go for the fiats. Even if it becomes stable, there would be a mass withdrawal which would still open it up to volatility.
Fiat also has no guarantee to always be stable because fiat can also be eroded in value by inflation and also by a sharp increase in the price of goods. And from several assets that I often monitor for their stability until now is gold because gold is still relied on by some people as a store of value that is so stable even though there are always increases and decreases in its price in a small percentage. As for Bitcoin, it is more of a future asset that can be relied on to be able to have sufficient profits after we collect it slowly through purchases.