I'd argue that writing Chef in Ruby (and Erlang) was absolutely to its detriment. Yeah, it was popular. It was also a debugging and scaling nightmare (not that Opscode helped that any).
In fact one of the reasons I rage quit megacorp for a second time was that I was required to use an Enterprise Chef instance that would log people out at random every 0-3600 seconds. I could throw plenty of deserved shade at my coworkers but Opscode didn't understand their product any better and I wasted more than enough time on conference calls with them.
I love ruby, and I'm using it for 18 years, but I've spent half a year on chef a decade ago and it was one of the worst wastes of time I had ever. Nothing to do with the language, everything to do with architecture of the thing.
Yes. Shopify, GitHub, Stripe, GitLab and more, but in large part due to Rails, not Ruby specifically (although Ruby is one of the great things about Rails).
It still is a slow language that does not offer anything over competitors that are an order of magnitude faster to justify its performance characteristics.
