IMO, still very much a licensing issue. Modern GPL3 GCC versions produce superior debuginfo as compared with Clang, in 2020, and the error messages and optimizations are currently competitive between the two. The ancient GPL2 GCC4.2.1 (C) compiled much faster than the modern Clang (C++), but I don't know if that still holds true for newer versions of GCC.

I have heard that the LLD (LLVM linker) is much faster than either ld.bfd or ld.gold.