yeshivishe kup: Osek until what point?
Are you asking in terms of time or accomplishment ? I assume all would agree that there is some Chiyuv to 1) know how to perform mitzvos properly, and 2) spend one’s time not otherwise taken up by earning a living, etc.. in the study of Torah. The latter would seem to serve several purposes, even if one studies those areas that are not “Nogei’ah L’Maaseh”, such as development of Midos Tovos, development of an appreciation for the “wisdom” of the Torah and of Chazal, and last but not least, to keep oneself occupied so he doesn’t do other things, V’HaMaivin Yavin.
Perhaps you are trying to distinguish between those who study Torah as a subject versus those who study Lishmah.