Perhaps a compromise or judicious position would be that anyone interested in democracy should pay attention to both left and conservative parties, though political sociologists often would rather study the left (myself included).

Mudge’s book is impressive in its scope with regards to years of history (about 1890 to 2005) and the number of countries she considers in narrative detail. The natural inclination for most sociologists would be to go straight to the major politicians and see what influenced them. Instead she focuses on the party theoreticians and major economists, which are the Ministers of Finance (Sweden and Germany),  the Chancellor of the Exchequer (UK), or Secretary of Treasury (US). She examines left party political platforms and this involves considerable translational efforts. She constructs a neoliberalism index for the center left and the center right, but only maps out the US figures for this. Otherwise, the scores are aggregated for bundles of countries in regime types. Her conclusions that party theoreticians abstained from intervention (circa 1920), party Keynesian economists fully embraced government intervention (circa 1960 but beginning in the 1930s), and transnational finance-oriented economists deregulated (circa 1995) is conclusively shown for the United Kingdom and Sweden.