That seems like a foolish opinion on any tool. I also disagree with your first point, pretty strongly. Ruby is still quite popular. It's also one of the higher paying technologies.
Do you have anything other than anecdotal experience to back that opinion up?
The only real argument I've heard against Ruby as a career move is that it requires you to compete with very experienced, high-quality developers for jobs.
Since I'm on the other side, higher salary means a problem.
As a programmer-mercenary, I am worked on a lot of projects. My experience with Ruby is less than pleased:
If the team knows Ruby then obviously it's the right choice but if not..
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