This just makes me think that either you are exaggerating a lot, or you were highly unproductive at the big company than most people.
In either cases, I end up not being able to take your comment seriously.
At a big company you are given a slice and you really have to push to get anything more. I've had the experience where no work is assigned because approving anything takes time and once the work comes it is extremely easy to finish immediately because you have sat through weeks of meetings reexplaining everything to different groups get approval to change a form.
At one startup by the end of the day I was already learning four different languages/tools.
Now I imagine places like fangs would be amazing places to learn. If you ever work in healthcare most of your day will be explaining why this is a small change / very safe and you learn very little.
At a startup you might get core technologies going in a month, while at a big tech company the timescale might be closer to years.
I worked at a startup and the focus was on the work. I got to make decisions on what to work with, what technologies to adopt, and then I had to get them running. I worked on core technologies.
At a large company you rarely get to do this. You usually have large systems in production, have very large teams, and get to work on an established code base adding a feature or fixing something.
An interesting exercise at a large company might be to look at the version control checkins from the beginnging. The features at the beginning of the log probably went in a lot faster from fewer contributors.