lon Musk offered to buy Twitter for $43 billion on Thursday, eliciting extreme reactions from some. Jeff Jarvis, a journalism professor at the City University of New York, compared the bid to the rise of the Nazis.

Jarvis is but one voice in a rising chorus of lamentation and outrage over the prospect of Twitter getting a makeover by Musk. The tech billionaire has criticized Twitter for its censorship and has expressed his intention to restore it as a "public square" for open debate. The idea is mortifying for some. But why?