That timeline correlates well with the corporatization of academic research timeline, which got started in the late 1970s, boomed in the 1980s and has steadily risen ever since. The emphasis in applied science is now on patents and return-on-investment, aka safe bets. This is certainly the direction that much of NIH fundings, as well as DOE funding, has taken. Part of this is that entrenched industries (natural gas and coal power, say), don't want federal funding going to disruptive competition (monocrystalline silicon PV development, say). This is reflected in how federal funds are distributed as well as what research programs are supported at the university level. For example, count the number of renewable energy departments in the USA academic system: miniscule funding -> no programs.

It can't all be blamed on corporatization, however. The control of funding agencies at the federal level by vested interests seems to be a major problem, i.e. innovative lines of research that threaten the status quo could threaten those cabals that control fund disbursement, so such efforts don't get funded. The stagnation of Alzheimer's research and the focus on the amyloid hypothesis seems to fall into this category. This kind of bureaucratic ossification is not new; the classic example is how Trofim Lysenko in the Soviet Union controlled the direction of agricultural research for about three decades, much to the detriment of the understanding of plant genetics and crop development research in the USSR over that period.

So it can be attributed to the rise of monopolistic corporatization on university campuses on one hand, and the growth of entrenched bureaucracies at the federal funding level on the other. Neither group wants the rug pulled out from under them by 'disruptive innovation'. There are many historical antecedents for this kind of situation, incidentally.