We all know that USDC (and any other stable coin on ETH except DAI for that matter) can pull the rug at any second for any reason or for no reason at all. Given the nature of this project which is based on devs anonymity, trustless approach and paving the way among other things, I think that relying on centralised solutions is a security issue. We should always rely on math alone and I am saying this being aware that DAI has its own issues which you can google.