I'm not convinced. I've written a great deal of software in C++ and MATLAB. I don't see what the big deal is either way. You say this thing has been "decided 20 years ago" (by whom?) but that's clearly not the case, as myriad languages that use 1-based indexing are in existence, continue to come into existence, and are used to great effect. You cite Djikstra's argument (well, you didn't actually cite it [1]) but his reasoning isn't exactly air tight; he appeals to subjective ideas of "ugliness" and "unnaturalness" and "preferences" and cites a single anecdote for Mesa as proof of his correctness, then dismisses FORTRAN, ALGOL, and PASCAL out of hand as a "pity". Again, I'm not convinced.
[1] https://www.cs.utexas.edu/users/EWD/transcriptions/EWD08xx/E...