But Ruby is more or less a "rapid development" environment.

You pay for quick development turn-around with machines.

Go is not in that kind of space as far as I know since, as I understand it, Go is sold as low-ish level language competing with C++ and C for system development. For something that would replace those languages, unexplained, systematic leaks would be bad (I mean, my C++ programs might leak but it's reasonably easy to discover why. That matters).