How do mid/late stage developers learn new languages/frameworks?
https://cacm.acm.org/magazines/2022/3/258914-technical-perspective-how-do-experts-learn-new-programming-languages/fulltext
https://cacm.acm.org/magazines/2022/3/258915-here-we-go-again/fulltext
(the first link references the second so one could start with the second link)
I have around 7 years or XP now, and have switched roles between the Java/Spring ecosystem to .NET and am now struggling with Ruby and Rails.
Before reading this article, I, too, thought that programming languages and frameworks are just tools, and that if you know the basics of one, you can easily switch between them. In practice, however, I have found that to not be true. Also, while learning new languages/frameworks is hard, it's twice as hard to do it on the job, where there is added pressure of delivering work items while paralleling learning things.
What are some techniques seasoned developers use to quickly pick up new languages and frameworks? And how do you juggle expectations with your bosses on delivery while you're doing this learning?