The article is about an internal kernel API: They can easily rename those, since they are not exposed to user-space.
But you seem to be talking about the kill command and/or the kill function, that are part of the POSIX and C standards, respectively. Renaming either would break a shit-ton of code, unless you merely aliased them. And while I agree that kill is a poor name, adding non-standard aliases doesn't really offer much benefit
At this point the people complaining about Rust at every opportunity have become more annoying than the "rewrite it in Rust" people ever were