For long, decentralized stablecoins have claimed to maintain their peg backed by either collaterized assets or algorithms. It's this point in time where a so-called decentralized stablecoin named "TerraUSD" lost its peg with no point for recovery within the short term. This is not the first time a decentralized stablecoin loses its peg, as a similar situation happened with NuBits (USNBT) some time ago. Even now, another decentralized stablecoin called "Neutrino USD" (USDN) lost it's 1:1 peg with the US Dollar.
With failed promises to maintain stability, does this means decentralized stablecoins are a failed experiment? If not, why? Do you think there's still room for improvement? Your input will be greatly appreciated. Thank you very much.

IMO, I believe in the saying that there's always a room for improvement, in that case, those so-called decentralized Stablecoins that you mentioned has been serve their purpose to send a strong message to other decentralized platforms to make sure that if they want to issue such a decentralized Stablecoin it should be pegged or back with stable asset just to make sure it was stable and can withstand any possible scenario or attacked! just like what happened to Terra Luna's UST Stablecoin. Anyway, some decentralized Stablecoin has remained strong and consistent for years already and DAI is one good example.