I downvoted because nowhere in the article did someone suggest that calling two personas Alice and Bob was racist or colonialist. That's an extrapolation you made on your own and makes no sense.

Suggesting other names than Alice and Bob is part of a drive to use more diverse examples. Security is not just for Alice and Bob, but also for Anita and Bilal, and many others.

Far from a new question, see also: https://www.schneier.com/blog/archives/2012/09/replacing_ali...