
The problem is the shim can end up getting baked into formula binaries (e.g. `flex`) or cause odd issues when mixed up with brew `m4`, e.g. https://github.com/Homebrew/homebrew-core/issues/180040
The problem is the shim can end up getting baked into formula binaries (e.g. `flex`) or cause odd issues when mixed up with brew `m4`, e.g. https://github.com/Homebrew/homebrew-core/issues/180040