It's interesting I think having an understanding of the history of javascript concurrency is almost a prerequisite to using it correctly. I wonder how new people approaching the language for the first time find it.
Camp 1 has the problem of continuously importing kitchen sinks instead of polyfills, which would allow getting into camp 2.
Camp 2 is essentially a luxury of time, thus rare. It already requires mental commitment, which may be scarce after a day of battling bugs for IE.