If you’re looking at something like Niche and their dot plots - at best it helps provide a sense for where you might be in the pool. It doesn’t consider all of the other factors that many schools weigh in much less the specific high school situation (elite private school? poorly ranked public school?). When people put their GPA’s into those things are they putting in UW or W? It gets squishy REAL FAST.
S23’s high school uses Naviance and there are dot plots in that system as well. For the schools that showed a representative sample of students that applied I felt like it was directionally accurate. The problem is that there might only be a handful of local schools with good sample sizes to gauge.
Like everything else - use it as one small tool/data point out of all the other data points you might be accumulating when forming your Reach/Target/Safety lists.