As the industry matures, the rise of cryptocurrencies that tracks the performance of less volatile traditional assets like real estates and commodities will likely bring a lot of beauty to the cryptocurrency industry. I believe that a mix of more volatile crypto assets and less volatile assets will give traders a lot of options to enjoy while trading.
I understand that you are trying to mean those cryptos which are based on real estates and commodities will bring another layer of volatility to crypto trading even cryptos themselves mature toward less volatile nature, right? But, we need to understand that how volatility of gold is still persisting even after centuries of trading; I mean there cannot be any mature level for assets as new adopters will be ready to offer good prices which will again keep them to fluctuate 
.I believe that a mix of more volatile crypto assets and less volatile assets will give traders a lot of options to enjoy while trading.
Some cryptos may find a relatively stable prices and may not forever. So, obviously we are going to have collection of all types of volatile crypto assets in our portfolio all the times. If you notice, all cryptos do not fluctuate all the times nor all do not fluctuate at a time. So, your portfolio will remain as mix of "everything".