The datasets/libraries/dictionaries for these algorithms are pretty generic (meaning its basically a sum of all the basses of datasets and the the median is the average of those sums of basses) (meaning it’s like the concept of averaging off numbers, where you’re giving a set of data numbers and you add each set of those numbers and the output would be the average sum of those numbers). With that concept in mind, most of basses (and I cant speak for every dataset because every dataset and algorithm is different) in today’s music (so for example deep sub basses) are different then the basses in music from the 70’s, music from the 70’s more-or-so were actual bass from a bass instrument or bass guitar or string bass (not an actual sine wave). Music in 2024 is more likely to use a deep sub bass (from a sine wave) rather than an actual acoustic bass.
One technique I use to unmix a clean bass (without interfering with the phase) is to duplicate the layer and transform the layer (by frequency shifting it) down in frequency. Remember the amount you transformed it down to, because you will have to transform it back in the bi-polar polar opposite direction. Once you transform it down, apply unmix (to the transformed layer) and it should output a clean unmix result of the bass. When the bass is unmixed, transform the layer back to its original state(in reverse bi-polar of the polar opposite you original transformed it by) then turn on the phase in that layer and merge the two and you should get a clean bass unmixed.