GPL has certainly failed time and time again, openly in the case of FFmpeg and their clones all over Eastern Europe and elsewhere. FFmpeg made a lot of noise and resorted to "public shaming" mostly because the courts weren't working for them. And they have a very visible product... so many GPL licensed things are lurking inside proprietary products where they'll never be seen.
It's like putting a license on COVID to prevent it from spreading... it just doesn't work in the real world.