Elon Musk's luck has finally run out

https://sh.itjust.works/post/10877329

Elon Musk's luck has finally run out - sh.itjust.works

Unrelated question!

In the phrase “He -and his empire- are showing[…]” as written in the title, should the “are” have been “is” or do the - instead of parenthesis mean we include the empire when we conjugate “to be”?

If two concepts are joined by “and” then prescriptively the article should be “is” not “are”. However most US speakers either don’t like the sound of that or don’t know the difference.
I’m asking because in this discussion case they added the em dashes (didn’t know that’s what they’re called) before and after “and his empire”, separating this part from the rest…

In this case they used the dashes for dramatic effect. It's sometimes used to mimic spoken English, in that the cadence of the sentence is changed by the information contained in the dashes. Often, it's replaced by commas in the form of a non-defining relative clause (The man, who lived in the house next to me for many years, was coming to visit). Think of it like a cue to take a pause before saying/reading the information.

Here's a link, if you want to read a bit more: https://writingcommons.org/section/grammar/mechanics/punctuation/dashes/

Dashes - Writing Commons

A dash (—) is a punctuation mark used to set off an idea within a sentence and may be used alone or in pairs. Dashes interrupt a thought in a more dramatic way than a phrase enclosed in commas, but less theatrically than parentheses. To form a dash, type two hyphens—without a space before, after,

Writing Commons

Interesting, I interpreted it as a replacement for parentheses instead of a replacement for commas.

Thanks!