[Pannoniae]

Basically, since the advent of bebop, the overwhelming majority of pianists use sparse comping. This means that they don't really provide bass, they just provide shell/rootless chords for themselves to play, the main focus is soloing in the right hand, or when others solo, just providing chords in pulses. The actual bass is provided by a double bass player, who plays a bassline.

Before that, the prevalent comping style in the left hand was stride, which provides a rich bass backing. (You know, the oom-pah stuff) Contrary to the common criticism, if coordinated well, this can also work in the presence of a double bass player (just check out Fats Waller recordings, many of his Rhythm recordings had a double bass player!)

[tunesmith]

This sounds more like the difference between playing solo and playing in a combo. If you're playing solo these days, you pretty much have to switch between a variety of these styles in an artful way (which I find really freaking difficult).

Even pre-bop, like singing Great American Songbook stuff while playing the piano, requires this. Like, for the head while you're singing you can get by on bass and chords while you sing the melody, but when it's time for your piano solo, you're basically trying to fit three responsibilities in two hands. Stride is only one way to do that, and you really only want hints of it.

[Pannoniae]

"and you really only want hints of it." What's wrong with full-on stride? Or using close-voiced four-to-the-bar chords? Or "mini-stride"? (Like stride but not moving the hand, only playing a chord broken up in the middle) Or mashing octaves/6ths in the left hand?