It is very scientifically based that people who often drink sodas have higher levels of cavities. Because the high pH dissolves small layers of the enamal which over time and with consistent use leads to weaker teeth.
You can find plenty of studies to support this.
Also how do you think people learn which foods give them acid reflux? Usually a combo of a well know list from the doctor or the internet, and then trial and error which is not fun or healthy.
Sure, it won't be a straight and simple indicator, but it helps. Like how you could probably read the fat content on a snack to know if it might trigger it.