Ignoring what "legally" forced entails, and just focusing on the mechanics of renaming stuff: Even if your code base can be updated with a simple "s/old/new/" regex (and, IME, this never, ever works as well as you thought it would, and always creates a long tail of manual grepping and editing), you still have to fix the docs, deal with breaking API changes, support multiple versions, provide upgrade paths, deal with confused users, etc. etc. etc.
And, um, confusingly, the examples you cite are actually even more complicated and work-intensive than what is being talked about in this article, because they also require URL / domain name updates, legal document changes, regulatory filings, etc. etc.
TLDR: the contention that "name changes happen easily" is not an accurate description of the situations you are citing.