I'm confused. Were you looking for a cryptocoin that was promising 1,500% gains?
Anyone promising a safe 15% return in a world where your savings account earns 0.15% interest is trying to rob you.
A company that couldn't get financing any other way could get financing by issuing fixed price convertible bonds. "Fixed price convertible" means the bond can be converted into shares (of the company), but at a fixed price - aka, regardless of the value of each individual share, you are promised fixed a dollar amount of them.
This means if the share price drops, you will be "made whole" by getting issued enough shares to match the fixed price.
It's called death spiral bond, because if/when the price of such a company drops, these convertible bonds will trigger, causing the amount of shares to increase (as they issue new shares), which in turn causes the price of the existing shares to drop, ad-infinitum. Often the owners of the shares would end up with nothing as the shares' value drops to zero (or the company recovers, and they do make some money).
Swap bonds with UST, and shares with Luna, and you get the above scenario.
Skipping the middleman is necessarily better because it is inherently lower risk for an absolute guarantee of 33% more upside.*
Investing in something else with even 16% promised returns, let alone 1500%, is not necessarily better because it is almost certainly higher risk.
* When Anchor (Luna/UST) crashed both StableGains and direct users of Anchor suffered the same percentage losses. But direct investors in Anchor had balances which were necessarily 33% ahead of StableGains investors due to not having StableGains shave off their interest earnings.
Stablegains had nothing going for it, in fact it had all of the risk with none of the reward. 1500% APYs are usually attached to LPs carrying huge risks of impermanent loss rather than stablecoin staking and are usually very transient in that they evaporate within hours.
FWIW I disagree with Anchor being termed a ponzi.