Great points. Yes, when a large number of users will hold a small amount of SP, Steem can easily reach high valuation. However, there will be always selling pressure since Steem is also meant to provide livings to large number of creators. And, DApps can fulfill this need too.

We also need a large number active and passive investors who sees Steem as a store of value similar to top cryptos such as BTC or LTC. They may not have enough time to curate but can delegate to projects or individual to earn TOKENs or Steem to increase the value of their investment.

Demand for Steem can come from minimum holding (500SP) for RC requirements to be active in many DApps, curation rewards, influence (self-vote in few blogs daily), earn TOKENs by delegation and most importantly, a strong store of value.

Currently, Steem is worse off as a store of value due to higher selling pressure which scares off many crypto-investors. And, investor class is the biggest driver of an asset's valuation.