How yield reaches you
Either the token balance rebases upward, or the token price appreciates against a stable reference, or distributions are paid separately. Each has different tax and accounting consequences depending on where you are.
The yield is the underlying rate minus management and custody fees, which can be a meaningful share when rates are low.
The structural layers
A fund or special-purpose vehicle holds the bills. A custodian holds the securities. A transfer agent or smart contract tracks token holders. A jurisdiction governs the arrangement.
Each layer is a dependency. The bills can be perfectly sound while the vehicle, the custodian or the legal wrapper is the problem.
Concentration is worth checking as well. Several of these products route through the same small set of custodians, administrators and transfer agents, so holding two different tokens can turn out to be one operational exposure wearing two different names.
Access restrictions
Many of these products are restricted to qualified or non-US investors, enforced on-chain through a permitted-address list. Transfers to unapproved addresses simply fail.
That is a compliance requirement rather than a defect, and it means the token is not freely transferable and secondary liquidity may be limited.
Redemption and liquidity
Redemption typically settles on a schedule matching the underlying market, not instantly, and may have minimums. Secondary market liquidity varies and can be thin.
FBT Swap displays market data for listed instruments with the source named. It does not issue or redeem tokenized treasuries, does not guarantee any rate, and shows an unavailable state rather than displaying a yield it cannot source.