[Cyncceply]

At least for the lower enlightened beings (eg. once-returner), in jhana, the mind is predominantly manifesting bliss thus it obviously has not reached the state of complete dispassion & pure clarity

Although insight (vipassana) obviously occurs in the jhanas (and before the jhanas), such insight is not sufficient to end the asavas (mental effluents), despite a sutta or two that may state otherwise

Thus a bifurcation occurs due to the predominance of samatha (tranquility) and the inadequecy of vipassana (insight)

Kind regards