Clang is targeting specific market - free and non-GPLv3 compiler (with OBJC support). The sales catchphrase superior error message is still true for the people

Clang is targeting specific market - free and non-GPLv3 compiler (with OBJC support). The sales catchphrase superior error message is still true for the people in the market. And comparison with compiler in GPLv3 is meaningless to them. You're just out of target.