Including package increases binary size by ~2,7MB

Just including the argument parser raises my CLI tool binary size from 250KB to about 3MB

This seems a _bit_ excessive.

**ArgumentParser version:** `main`
**Swift version:** Apple Swift version 5.3.2 (swiftlang-1200.0.45 clang-1200.0.32.28) Target: arm64-apple-darwin20.3.0

Start by reproducing the reported size change with a minimal CLI tool using ArgumentParser at version main, on Swift 5.3.2 if possible. Compare the resulting binaries to isolate the source of the increase; done should be a documented explanation and an agreed reduction or determination that the size is expected.

Written by the indexing model from the issue text.