I think he meant to say "A good reason to encrypt your archives", not just put a password on them. If you encrypt your archive, even a rar, gmail shouldn't be able to see the contents inside of it.
Another solution is to simply change executable names to .exe.backup or something similar, that way it'll register as a ".backup" extension for most systems and not be blocked simply by name (though this wouldn't necessarily defeat things that actually detect and block binary executables).
At least with .rar files you can still see the list of files in the archive even if it's password protected.
I think he meant to say "A good reason to encrypt your archives", not just put a password on them. If you encrypt your archive, even a rar, gmail shouldn't be able to see the contents inside of it.
Another solution is to simply change executable names to .exe.backup or something similar, that way it'll register as a ".backup" extension for most systems and not be blocked simply by name (though this wouldn't necessarily defeat things that actually detect and block binary executables).