Technical issues were another reason; Stallman intentionally made GCC worse to prevent possible abuse (mostly based on unfounded fears, IMHO), some GNU tools are not well suited for all environments ("bloated", for lack of a better term), and there have been some governance issues (e.g. GNU libc was notorious for a long time, but also copyright assignments to the FSF, bad technical decisions being made for purely ideological reasons).
Also, Apple pretty much proposed to transfer LLVM to the FSF: "If people are seriously in favor of LLVM being a long-term part of GCC, I personally believe that the LLVM community would agree to assign the copyright of LLVM itself to the FSF and we can work through these details."[1] which was basically just ignored. That was in 2005 before GPLv3, but it shows that Apple wasn't against copyleft out of principle and that a small bit of pragmatism would have prevented the alienation of Apple, as well as many other organisations and people. All that for the very small benefit the controversial clauses in GPLv3 give us. Well done people.
Also, Apple pretty much proposed to transfer LLVM to the FSF: "If people are seriously in favor of LLVM being a long-term part of GCC, I personally believe that the LLVM community would agree to assign the copyright of LLVM itself to the FSF and we can work through these details."[1] which was basically just ignored. That was in 2005 before GPLv3, but it shows that Apple wasn't against copyleft out of principle and that a small bit of pragmatism would have prevented the alienation of Apple, as well as many other organisations and people. All that for the very small benefit the controversial clauses in GPLv3 give us. Well done people.
[1]: https://gcc.gnu.org/legacy-ml/gcc/2005-11/msg00888.html