[electric_sheep]

Way I see it is it's more than OK to not know things -- it's a necessary optimization. Engineering is all about tradeoffs, and skills development is no exception. Follow one path, forego another; dive deep, sacrifice breadth (and vice versa).

So consider that maybe, just maybe, for a developer working full-time on a SPA framework, not knowing Docker or Bash scripting might not be a real impediment to working effectively or delivering quality product. If it were, perhaps React & Redux wouldn't be as great as they are. And since they are great, maybe we should consider that fact not as a celebrity get-out-of-jail-free card, but as counterevidence to your implication that these topics all constitute a universal educational imperative, and that someone lacking in any of these areas is by definition not a professional in the software field.