This "user friendly" behavior is actually detrimental. pkg-config is very often wrapped in a shell script of cross-compiling toolchains. Such wrappers may pass extra arguments, such as --static, (reasonably) not expecting that to break --version. Some build systems (meson being one example) use --version to determine whether pkg-config is usable. Naturally, the wrappers fail this test, even though they would've worked with the original pkg-config.
We will drop this in 2.0, but shell scripts should be replaced with personality files instead.
Resolved by commit 62bbd3b664d4b03011a4b382ed20353a91c30406.