It's not naive – naive is believing Linux' success comes only from GPL. That's ridiculous. Windows sells like crazy too, does that make its license the nonplusultra?
Linux booms because of Open Source (not just GPL), sponsoring (IBM, RedHat), thousands of volunteers, and pure luck. Without GPL? Sure, some BSD-derivative would've eaten that niche.
GCC? Without GPL we'd have more compilers – not just one monopolist. You're confusing protection with innovation death.