With all due respect, I would strongly disagree here. Rails is big, for sure. But beyond that there is soo much going on at the language level (best example here are the awesome folks working on MRI and Rubinius), Ruby (not Rails) is taught in universities today, we have strong companies backing all sorts of Ruby craziness (check the weekly GitHub newsletter and their staff picks) and last but not least Rails itself is helping the development of core Ruby by its sheer size and it's excellent habit of trying to target the latest Ruby versions with every new release, these days.

Don't get me wrong, there definitively is way to improve and make people more aware of how Ruby can be outside of Rails but I don't think Rails is poisoning our ecosystem, quite to the contrary it is one of Ruby's biggest asset.

Every language has it's chasms. Python seems to split on 2 vs. 3, JS can't decide on a solid tool chain for longer than 3 weeks and Ruby has the big Rails/Ruby divide. Only thing we can do is embrace diversity and create opportunities for those in the other camp to tinker with some of the things we love.