For overwhelming majority of startups hardware is a tiny fraction of their operating costs.
Not to mention that a lot of the hardware costs are language-agnostic: database servers, disk volume.
Not to mention that a lot of the hardware costs are language-agnostic: database servers, disk volume.
You can easily reach "scale" (earn millions of dollars, serve millions of customers) while still running on 2-4 web servers.
But I've done it with Python and I can't see why Ruby would be any different.
Why is that so surprising? Nobody sane does anything CPU-intensive in their webapps.