What I hadn't realised was that that the displacement of the generalist had in the nineteenth-century given rise to such potent ideologies of frustration. Here's Kevin Passmore in his excellent Fascism: A Very Short Introduction:
[The late nineteenth-century] saw the emergence of modern disciplines in the universities: history, sociology, political science, physics, biology, literary criticism, and so on. The rise of professional, specialized research led to displacement of old-style scholars, sometimes amateurs, who claimed expertise in several fields. Lawyers and doctors, who had previously dominated university faculties, were especially likely to pretend to wide competence, and were attracted to ... racist, eugenicist, psychological, and historical ideas ...If any reviews of my book complain that it attempts to be too far-ranging, I'll be careful not to take the criticism to heart!
These polymaths often resented their lack of recognition from specialist professional academics, and compensated by seeking political success. Some favoured the extreme left (the legally trained Lenin was a quintessential generalist); others the new right. [Maurice] Barrès gave the [French] republican establishment's refusal to honour a now forgotten race theorist as a reason for entering politics. It is no accident that doctors and lawyers were prominent in the far right. Their resentment of specialists was coupled with fear that professions were overcrowded with Jews and women, and with dislike of government plans to introduce ‘socialist’ health-care programmes. Doctors and lawyers espoused eugenicist theories, which they thought gave them the right to play god. Specialist academics were often just as influenced by pseudo-scientific knowledge and nationalism. In pre-war ultranationalist movements specialists sometimes held sway, but generalists with chips on their shoulders increasingly set the agenda. [p. 38].