I'm looking for the following sources, I searched for it, but unfortunately can't find them on HebrewBooks (might be my mistake though)
Igros Moshe, Orach Chayim 1:20 by R'Moshe Feinstein, in which he explains that they (the people in the generation in which the Second Holy Temple was destroyed) did not make a blessing on learning Torah (Eicha Rabba) - which means they did not relate to learning Torah as a mitzvah in its own right, but only as a means to knowing what to do. They failed to see the intrinsic value in learning Torah (see this post).
Torat Menachem, vol. 27, p. 108-113, in which it is explained that the issue was not so much the blessing, but what it represents, e.g. if one learns Torah as an academic pursuit.