Please link to where I said not to use copyleft licenses. Check the usernames carefully.
Note that I don't agree that GPL and MIT are equivalent, or that GPL becomes a non-copyleft open source license if not enforceable. IANAL but it might revert to the regular copyright law for wherever you publish software, not an open source license.
just be honest, you don't like GPL. The reason you don't like GPL is not because it's not enforceable, but because you don't want to enforce it, or be subject to its strictures. Your argument that you use MIT because GPL is unenforceable makes no sense, as I pointed out.
(also, it is enforceable and has been enforced, but that's a separate topic.)
Note that I don't agree that GPL and MIT are equivalent, or that GPL becomes a non-copyleft open source license if not enforceable. IANAL but it might revert to the regular copyright law for wherever you publish software, not an open source license.