I mean, Tron chain itself is not freezable, it's in the smart contract logic. Same picture for USDC. But yes, I have no idea what to use instead of USDT-TRC20 yet, and Ethereum chain is too greedy in terms of fees IMO.
Solana tokens are all freezable by design as far as I see.
I wasn't implying Tron was freezable I was speaking about blockchains in general. Yea, ETH too expensive to use all the time or for small amounts. You can use DAI on ETH L2s but those are all ruggable (but still permissionless. i think?). I'm just barely starting to look into Solana, but I think you are right.
You can also weigh the risks and just continue using USDT on Tron for now. Not ideal, but I think freezes are still pretty rare so very unlikely to happen to you (but they are getting relatively more frequent). I wouldn't keep any major amounts on it though of course.