You are right in some sense but IMO, sound money is a wealth backed by things with real value, wherein the thing that backs it won't lose value easily in this period and it does not go up and down in price rapidly. You can refer to gold and anything backed by it as a safe money, so long as it doesn't always decrease or increase in value. You can also say the same with other precious metals and anything backed by it(I might be wrong though since this is based purely from my opinion of it).
The Monetary Eco-System must be Trustless, Decentralized, Anonymized and 'Secured' by Validated Eco-System GDP. Driving Rate of Adoption, Fungibility, Network Services, Exchange and Utility Values.
Eco-System-GDP is Defined and Measured as: Authenticated Cash and Cash Equivalents from Operations, Modest Earnings Margin/Growth Multiple + Audited Net Asset Value (NAV) of Portfolio Holdings; land, buildings, equipment, finished goods inventory, natural resources, etc.
A Cryptocurrency Ecosystem or Cryptosphere Capable of Meeting the Needs of Hundreds of Millions of Consumers, Traders and Trans-Actors on a Truly Global Scale.
As the number of users increases, the system becomes even more valuable and is able to attract and retain a resilient high-quality stakeholder base, organically growing the networks Member Service and Utility Values.
A key concern must then be how to attract early adopters and opinion leaders prior to reaching critical mass.
The key strategy here is to create a system that builds-in enough tangible and experiential value, to early adopters, without significant network effects at the outset.