It takes a few hours to learn to use the tools mentioned in the article (and many similar ones) to a level of competence - part of the appeal is how easy they are to use. It takes a few hours to learn how to get new data into and out of them as well. Both are the sort of thing taught in 45 minutes presentations and workshops during the Bootcamp training at FB, and then most people can just explore the rest themselves over time in normal usage.
What takes months is feeling like you understand the most important tools and aspects of the environment to be as effective in them as those around you, or to match how you felt in an environment where the scope is smaller. It’s not like you’re sitting in classes for months - you’re doing your job (maybe even more effectively than normal due to the availability of these tools), but every once in a while you’re encountering something where you need to ask someone else or explore or watch a video about how to do something, and that might break your momentum.
What takes months is feeling like you understand the most important tools and aspects of the environment to be as effective in them as those around you, or to match how you felt in an environment where the scope is smaller. It’s not like you’re sitting in classes for months - you’re doing your job (maybe even more effectively than normal due to the availability of these tools), but every once in a while you’re encountering something where you need to ask someone else or explore or watch a video about how to do something, and that might break your momentum.