[jjice]

> Coming from web dev, I used to volunteer to dive into a Objective C repo to fix some random bug in a mobile app

The thing about this is that this isn't just a language change, this is an ecosystem change. It's one thing to go from writing Python based web apps to Ruby based ones, because web dev has a lot of concepts that will apply no matter the language. Objective C might be something you can pick up no problem, but having the learn all about mobile development and that ecosystem is a much larger task, and I could absolutely see that getting exhausting if you're hopping from web, to mobile, to desktop, to embedded, etc.

Ecosystem switching requires a lot more of a knowledge shift than just a language does, IMO.

[wizofaus]

I'd agree with that. I even think the difference between frontend JS development and backend JS development is bigger than, say, backend Java and JS development. But managers, even ones with tech backgrounds, tend to assume the language is the key skill. A good developer should be able to master a couple of different ecosystems given enough time but expecting them to constantly jump between them is never going to lead to great results.