[yusefnapora]

Why would you assume that, because they wrote an alternative to an existing tool, they don't know how to use it? Perhaps she just doesn't like sed, or would like to use the replace functionality in an environment where it's not clear ahead of time whether GNU or BSD sed are available. Or any of a number of reasons. Your assumption that she must be ignorant to have created her own solution is just as boorish as the original tweets, imo. Was tmux written by a person who had "either never heard of or never learned how to use" GNU screen? What about GNU itself? Why bother when UNIX already exists? People have lots of reasons for writing software, and deciding for them whether it's "the right thing to do" because some other software already exists is absurd.