USDT is the worst in this regard since you have to deal in massive volume. The minimum withdrawal is $100k and fee on that is the greater of $1000 or 0.1%.
That seems like a fair policy to avoid getting DDoSed by withdrawals in periods of high demand (i.e. bank runs). Presumably they mainly intend to serve exchanges which are doing withdrawals in the $millions.
https://tether.to/en/fees/