Regardless of supply, USDT is by far the most popular stablecoin. And USDT has the most trading pairs of all centralized exchanges, and I have seen that almost all crypto users transact a lot of USDT. CoinMarketCap analysis shows that USDT has a much higher supply than USDC, yet they are able to keep their ratio at 1:1. So for me, USDT is definitely the best.
I share a similar view. I love USDT for its popularity and Tether groundbreaking ideas in this market. However, many investors prefer USDC because Coinbase & Circle are more reputable and have better regulatory compliance than Tether.
Currently, Tether is trying to comply with the law and provide better audit proofs. I hope they succeed and continue to maintain their leading position in the stablecoin sector. As long as Tether keeps minting more USDT, I remain optimistic about the growth of the crypto market ^^