Thousands of coins do not giveaway half their supply to existing holders without asking for anything in return. How do you expect an outside investor to see that as a viable basis for parking their capital ?
All Dash had to do was tighten up its protocol allocation to such non-performing drains and the capital losses (which, ironically, were disproportionately suffered by masternodes) could have been avoided.
Remarkable that years have passed yet you keep repeating the same message without ever grasping that the dynamic you describe has already been baked into valuation for quite some time.
Instead of worrying about Dash as an investment vehicle you should simply consider using it for its primary intention - a currency - or else just stop worrying about it.
If you can't, perhaps consider appealing to those who can actually do something about the "problem" rather than restating it here for what is likely to be the hundredth time.