As far as the Vilna Gaon’s position on secular studies:
The GRA held that objective knowledge (i.e. mathematics and certain sciences) could be studied for the purposes of enhancing one’s Torah understanding. He most certainly did not allow studying secular subjects “for its own sake.”
In fact, in the aforementioned Shulchan Aruch/Rama I quoted, it is the GRA himself who approvingly comments that the source of the prohibition of studying secular knowledge for non-parnasa type reasons, is from the Yerushalmi!!
The bottom line is, NO ONE disagrees with the aforementioned Rama.