Stablecoin redemption

While it's well-known that USDT and USDC are fully backed, the process of buying or redeeming these stablecoins directly from the issuers, like Circle for USDC or Tether for USDT, is less commonly discussed.

Have individuals succeeded or even attempted to purchase or redeem these stablecoins directly from their respective issuers, bypassing exchanges or third-party services?

For instance, have there been successful cases of buying or selling USDC directly from Circle or USDT directly from Tether by individuals?

This direct interaction is a crucial aspect to consider when evaluating the liquidity and accessibility of stablecoins.