What's the purpose of the

sg13g2_io_notracks.lef

file and is this actually used in designs?

The LEF views were autogenerated using

PDKMaster

tool from @FatsieFS. Since this file does not define actual shapes on the metal layers I suppose it was used mainly for debugging the development process of the IO cells, but it is only my supposition.

That’s what I think too. Thanks!