GUSD and USDC are different in several aspects. In terms of reserves and liquidity, while only about 60% of the reserves of USDC are in cash, leaving the rest in bonds and debt securities, the reserve of the GUSD is audited every month.
In addition, the market capitalization of USDC is largely higher than that of GUSD. As of January 2023, the market capitalization of USDC was over 3 billion more than that of GUSD, at 43.21 billion and 622.883 million, respectively, according to Yahoo! Finance.