This file was read in as a sort of lookup table for what projection to use on the .prj file's WKT PROJCS field. E.g., if a .prj file's WKT had PROJCS["WGS 84 / UTM zone 10S", it would be associated with "<32710> +proj=utm +zone=10 +south +ellps=WGS84 +datum=WGS84 +units=m +no_defs no_defs <>" from the ESRI file, and the various attributes would be parsed out (+proj, +zone, etc) and used to construct an mstruct.
As of 2020b PR, the ESRI file seem to have been removed, and shaperead2 fails to work as it required that ESRI file.
I've tried looking for any mapping toolbox related functions that might have been added to fill the gap, such as something that reads from the new proj.db SQLite database and possibly does an alias to projection lookup, but I haven't found anything.
What do I have to do moving forward to get this to work in 2020b and on?