Bitcoin, the "older brother" to all other cryptos out there has been around for nearly 9 years and has been declining in volatility.
Here's a site that tracks 30 and 60 day rolling values -- https://www.buybitcoinworldwide.com/volatility-index/
It shows that even though we're in a 4% range, it still isn't too far removed from Forex traded currencies or other financial instruments. This will only improve as further inroads are made with users.