Some excellent points made, especially as this pertains to arranger keyboards . . . I rarely will do a walking left hand bass unless the particular jazz song calls out for it . . . There are some styles that do provide a really nice bass line with the arranger, and then my left hand can focus on many other things! Now, on a piano, that’s a different story . . . But again, depends on the song and the style for me.
I also played accordion for a few years, loved it!!!