The most influential change has been the increase in competition for resources in academia, especially via grants and similar competitive funding (to both researchers/research teams and to universities themselves) [1]. The idea that competition breeds efficiency is a core tenet of (neo)liberalism.
There has been a concurrent shift towards bibliometric assesment of researchers and institutions, to a large part to have metrics for the competition.
In general this is largely an application of the (neoliberal) New Public Management [2] model applied to academia and science.
Before this shift funding was based mostly on budgets akin to how e.g. schools or (public) healthcare and police are funded. Academics were mostly just hired to a (permanent contract) job when there was an opening. Anecdotally, my supervising professor was tenured almost straight after he got his PhD in the 1970s. And he didn't really have to apply for competitive funding until 2000's or so. And this was more or less the norm back then.
In angloamerican countries the neoliberal turn started already in the 1970s. Although there was also a contemporary explosion in funding of science much due to the role of scientific and technological progress in the Cold War.
The degree inflation likely plays a role too, and in research this shows as more PhD students who have to churn out papers to get their degrees (which is beneficial to the universities as they are assessed on how many affiliated publications they output). There's of course plenty of quality PhD-level research but it's also quite obvious that the quality is also affected by the students still essentially learning the ropes.
Academia's, science's and higher education's societial position and "clout" was quite different and smaller in the era of classical liberalism (roughly until WW1), and public funding had a lot smaller role.
It's of course totally arguable that competition leads to more efficiency. However, the academic world doesn't really have a natural market and establishing comparative value of different lines of research, academic institutions or individual researchers is very difficult. And due to this the resource allocation is done largely based on quantity of scholarly outputs (papers and PhD degrees) and salesmanship. These of course are very easy to play, and those who don't engage in the play tend to not survive. And it adds huge overheads.
[1] https://link.springer.com/article/10.1007/s10734-008-9169-6
[2] https://en.m.wikipedia.org/wiki/New_Public_Management