I recall that folks did analyze this, every server running in production has its flags logged, and every command line tool run on user workstations is also logg

I recall that folks did analyze this, every server running in production has its flags logged, and every command line tool run on user workstations is also logged. Then it's just a matter of having a registry of every flag (aka the source code) and diffing the set of flags used vs declared. As you would imagine most flags were never used. Now removing them is another thing entirely -- but some teams do have code cleanup fixits. Yes it does make source code smaller and simplier to read. But if you're referring to binary code size - well it pales in comparison to what protobuf contributes to generated code size. I'd say that proto code makes up >60% of Google binary size.