The biggest scam Stablegains pulled was to advertise taking USDC (most trusted stablecoin, backed by real, audited reserves), as to imply they were providing USDC lending yield, when in reality they converted your money to UST funny money.
> Until March 2020, the attestations said USDC was backed by dollars, held in government-backed US depository institutions. After that, they said the reserves were held at institutions and in “approved investments”, but did not give precise details about what those investments were. By June, it changed the wording on its website from “backed by US dollars” to “backed by fully reserved assets”.
so, you can have that honest 2% per year for several years or you can just take it all almost immediately. History as well as crypto today is pretty clear about what humans prefer. Absent the "take it all immediately" option people do though go for the 2% option. So if you see that they can go for such an option and yet haven't - i.e. they think they have a much better option than to earn easy 2% off somebody's billions (what can be better than that?) - that is a clear sign what option they really chose :)
USDC has been audited yearly since 2018 as part of Circle's financial statements, with years 2020 and 2021 publicly available with the SEC: https://www.circle.com/blog/how-to-build-trust-usdc-audits-a...
Circle also does monthly attestations - independent, signed reviews by third party accountants - on USDC holdings. Those are available here: https://www.circle.com/en/usdc#transparency
I looked and the April '22 attestation seemed fine.
Even the FT article seems to walk back its claims about changes in the attestations as worrying, seems like their source actually is more concerned about digital currencies in general:
> “The problem to me isn’t the specifics of any one attestation, it’s the fundamental workings of these kinds of systems,” said Grey.