Jafant - remember, I'm not an engineer; my experience is more as an observer - user. Slew rate still gets lots of attention in professional audio, especially microphones and their preamps, but it doesn't show up much in print. I have Tom Jung's original Studio Technologies Mic Pre which was reworked by Jim Williams (pro geek guru) to upgrade caps, etc. He increased the slew rate by 5x as part of his magic. The preamp improved its transparency substantially, but lots of things were done at the same time, so I can't attribute any specifics. I wonder out-loud whether slew rate gets less attention now because it is generally faster now than in the old days. Also, I can only speculate as to Power vs Pre amp importance, but I suspect SR is important everywhere equally. Some amps like Spectral place storage caps right next to the output transistors to increase slew rate substantially by purely geographical means.
My observations over the years includes SR being a major factor in transient performance and therefore detail retrieval.