Dante and Beatrice had different targets for cultivation in the first place. For Beatrice, her goal was to use the energy gathering of the cultivation system to store enough energy to catalyze her Origin Core when the time was right.
She intended to cultivate right from the start of Qi Condensation and dutifully got through all the stages and converted her spirit energy into Immortal qi at the peak of the world's realm before using it and the multitude of energy here to do what needed to be done.
As for Dante, he already produced energy internally that surpassed the purest immortal qi in existence. He would be dirtying himself to absorb more and condense it the way cultivators do, so he was not focused on that aspect.