Umm...pointing to facts based on real data isn't bitter. Did you see even look at the graph that was shared? It's pretty clear ruby is trending downward and I say this as a past long-time ruby advocate and fan.
I think that you're conflating correlation with causation. I think it's more plausible to assume it was the early numbers that are skewed and non-representative.
The fact that GitHub itself was is a killer app of the Ruby on Rails, and that the Rails project itself changed to being hosted on GitHub somewhat very early on it's history [1] had a disproportionate effect on the early community that gathered there.
Now GitHub attracts a much more diverse portfolio of projects, so the numbers you see there are less statistically biased towards early Ruby on Rails adopters.