Although I have mixed feelings about emerging adulthood as a life stage, one more point in defense of it: calling it a life stage would probably steer upper-middle-class kids from going to law school simply because they feel like a soft landing into the entry level market isn't possible.
I've seen this dynamic play out several times something like this: college senior in college is uncertain about what to do with his life. He finds the entry-level job market complicated and confusing. Unless he's an engineer or able to get a fancy consulting or i-banking job, he probably can't make much money in an entry-level job either. This seems dispiriting. Having to work in an unpaid or barely paying internship for a few months after graduation would be even more appalling. So, even though many of these people could *eventually* hit pretty decent incomes working in non-profits or Hill jobs or art galleries, they panic and feel like they have to run off to law school or medical school.
I've also observed plenty of upper-middle-class parents who have weird attitudes about helping kids out financially in these situations. Helping out with law school tuition, no problem. Helping out with rent for three months while Junior establishes himself in an entry level job... that's off bounds, because Junior is supposed to be an adult now and responsible for all such expenses. This even though the latter would be much cheaper for the parents in the short and possibly also long run.
Some of these kids wind up loving the law. But too many of them don't and wind up merely irking their fellow students and colleagues. Too many of them wash out of the law altogether a few years in. Giving these people a few years of socially approved "emerging adulthood" to think through their choices to go to law school would be advisable. And to some extent, this already happens -- plenty of big firms bring on paralegals for two years who are doing just this. But I've encountered at least a few parents and prospective pre-laws who still seem skeptical of the wisdom of doing this. Seeing more acceptance at the margin for these options would be great.