However, I am still an investor, with legitimate concerns about the model's sustainability.
You said in an earlier reply to mine that the masternode threshold was "too high" for you. But you must acknowledge that that threshold (in terms of financial cost) has been set by the market, not by the blockchain designers. The 1000 Dash is arbitrary and there for a purpose (to mitigate the propensity to sybil attack the network). The market then puts a dollar price on that and if the asset is in demand that price will rise which was the objective of the whole plan in the first place. That fact alone should mitigate some of your concerns about "sustainability".
Now lets wind forward a bit. It's 2020, the credit markets have imploded, cash got banned, the crypto-sphere is gigantic and there are a myriad of cryptocurrency asset types out there all serving different types of currency market.
Dash's marketcap is not one of the leading ones, just the size of a moderate internet stock today - let's say LinkedIn at $15B which is only 1 twentieth of Facebook's.
That would value the collateral for a single masternode at around $2.5 million dollars and the associated revenue stream at between a $100,000 and a quarter of a million dollars per year depending on emission rates at that time. Thousands of investors benefit from a masternode revenue stream and also from second level business models like the one described in one of the current blockchain
budget proposals but none of them hold anywhere near the full collateral themselves, they are simply invested in all kinds of trusts and share products which are capitalised using Dash as their base asset. Furthermore, anyone who DOES actually hold Dash themselves in any quantity is quids-in because although their holding may not contribute to an active collateral base itself, it doesn't matter. It carries exactly the same value as the parts of the coin supply that do due to being in demand for either masternode collateral or trading currency.
It's all relative. We can't take today's values and project them onto tomorrow. The barrier to entry is 1 Dash right now and that gives you a theoretical 0.1% of masternode collateral which is how your holding will be valued, whether it's actually collateralising a node or simply decorating your wallet.
Masternodes are a great innovation in crypto. They solve lots of problems and add value at the same time. Hey, I think the barrier to entry on a
Falcon 7X is too high and those things can't even be sybil attacked !@!