Why do cars still have RPM gauges, i.e., tachometers? Who uses that info these days? In the olden days when I learned to shift, it was slightly useful if the radio was too loud to hear the engine.
For looks, to keep the dash symmetrical.
Well, me for one. I used the tachs in all my manual transmission vehicles and a couple of automatics as well. Lots of information available in just a glance.
Proper idle speed
Proper shift points on manuals, automatics, and manual shift automatics
Transmission or clutch slipping
Proper engagement of overdrive
Just to name a few.