After a while, the price would "stick". People wouldn't put fortunes in it, they would only acquire what they need to use as a currency. They wouldn't be watching coinmarketcap to see what goes up and what goes down. It would just be a real currency.
This is just pure speculation.
In fact, almost all altcoins follow the exact opposite pattern to what you've described. They launch, and price rallies massively, then they slowly tail off down to effectively 0. There are exceptions, but most follow this pattern.
You need a nash equilibrium in order to create a stable-coin. What you are proposing does not constitute one, or at least it fails to address reduction in valuation.