The other big theories aren't completely untestable, the issue is basically that the models have a lot of parameters which can often be tuned in a way that leav

The other big theories aren't completely untestable, the issue is basically that the models have a lot of parameters which can often be tuned in a way that leaves a possibility for the general theory to still work, and testing them to the point that any corrections seem too unreasonable is even more difficult and expensive.