Just my opinion:
Law isn't a shortage profession. It's oversaturated and competitive. There are thousands of new law graduates produced every year, very few of them will be accepted onto training schemes to qualify. Many from my university (I did accountancy) had to work as paralegals etc, some carried on as that after a couple of years, others moved on to other professions.
Of course few make big money but I don't consider it 'easy'.
Medicine is a shortage profession all over the world. Obviously. But the degree intake is restricted in the first place. And it takes decades of exams etc to qualify.
Accountancy - similar shortage. Even though the degree intake isn't restricted the big4 accountancy firms alone hire hundreds of new trainees each. Every year. And not even with accountancy degrees! Across all UK regions. Once you pass the exams and qualify as a Chartered accountant many doors are open. And if you don't make the Big4 there are lots of other smaller firms.
Of course those who are truly passionate will follow their path but for those of us who need money to eat and pay rent it's about financial security first and foremost. I consider law similar to investment banking (although the latter is much harder). Great if you can get it, but not as easy as the rest. Attitude of colleagues, yes, but also because of the nature of the profession.
FYI I also think that TV law shows portray the legal profession in a more exciting manner than it really is. It made loads of people want to become lawyers, have fun and earn the big bucks. While people still think accountancy is boring. Law is also the default 'academic yet professional' humanities degree when a lot of people don't know what they want to do, they study Law. Oxbridge has Law but not Accountancy or even Finance as an undergraduate degree.