Fortran predates C, so 1-based indexing has been “here” arguably longer than 0-based indexing. Most languages targeted at numerical computing use 1-based indexing because mathematics uses 1-based indexing in linear algebra. That seems like a huge benefit to me! C has 0-based indexing precisely because it doesn’t have genuine multi-dimensional arrays and has to use pointer arithmetics instead (which in my opinion makes it a very bad fit for scientific computing)