The esoteric bits of knowledge that are so criticized in that thread are what make med school what it is. They consider that to be fluff? People amaze me - they criticize ancillary professions in medicine for getting too much responsibility (NPs, PAs) for their level of training yet want to dumb down their own education so that they can get more "on the job" experience? It is pure lunacy to speak that argument and then go on and rail against "midlevel encroachment." Med schools are not cutting away the fat of the curriculum - they are cutting away the lean stuff and adding more fat. People like to just fall back on the argument that "none of that stuff matters" and that they can go look it up if they have trouble. But the problem is if you don't learn it and know about it then looking it up becomes a problem in terms of understanding what it is you're looking up.
In an ideal world, every specialty of medicine would have its own designed four year (or less) med school curriculum. But it can't work that way, because we can't force people to decide on a specialty before they know what they're getting into. Yes, the JAK-Stat pathway doesn't really matter to most EM physicians. But it matters a lot to internists, pathologists, and hematologists. The brachial plexus doesn't matter to me at all, but we shouldn't stop teaching about it.