[mrighele]

I don't think being 1-indexed is what made the reason.

While it was already in widespread use, Python really took off in the scientific/research community, thanks first to numpy and then to all the other libraries built on top of it up to the current crop of ML/AI libraries.

Those people used to write a lot code in Fortran, Matlab and R (depending on their research area) which are all 1-indexed.