While I don't use semicolons often, to me they are useful for three things: ordered lists, where options are related or parenthetical; to conjoin or inline an example; or a kind of silent differential to orient the idea in a paragraph in a new direction. It's not relevant in business anymore, but useful in tech writing.

In business, the tone and style of email is all about affecting power in environments where people pretend there are no rules that would imply accountability. The result is an absurd competition of who can be more brief, less coherent, and affect the ostentatious transfer of the burden of comprehension to the bottom dog.