Nobody used Ruby before that.
And I mean "yum" popular. Blender popular. QGIS popular. Not "that script that sort my ssh connection is in Ruby" popular.
How is that relevant? The question was what justified Ruby at the time.
If "Ruby on Rails" was the only justification, why did people use it for the 10 years prior to that? Were they not justified in using it? That's just nonsense.