> Lately I've confirmed its because they know exactly 1 language , but they know it so well & in so much depth, they know exactly where to look, the right mcmc

> Lately I've confirmed its because they know exactly 1 language , but they know it so well & in so much depth, they know exactly where to look, the right mcmc library, the right slice sampler, the right optimizer, that's what matters. It sounds to me like you're working in a highly specialized area that requires deep domain knowledge and rich set of tools to apply that knowledge. Your colleagues have a lot of familiarity with that domain and those tools. Knowing multiple languages isn't your problem, it's just that you haven't spent your entire career working in this particular domain and you're playing catch-up.