@Claude31 I have no problem on the Android side, only iOS. It's probably some issue with one of the xcode's project configuration file, but since it's apparently too much to ask that program to give a proper error message, I don't what the problem is, or what to do about it...

Yes. You need to run your Terminal with Rosetta (Get Info, then check the box), and then run your build command from there. If your Mac has an M1 chip and you want to do mobile development, you need to run pretty much every program with Rosetta, or you'll be swarmed by errors with every command.