The current post title “For the first time, the state of California was 100% powered by solar+batteries for a full 24 hour period.”
Doesn’t match the article title/headline
And the article doesn’t imply what the current post title says:
sunlight at least partially powered the state for well beyond 24 hours straight.
Just below the above quoted part, the article has a graph detailing how much of the power supplied was solar vs other sources over the course of that day.
If you use a real computer, making an em dash is trivially easy in Outlook and Word. Many people probably do it without knowing what it’s called.
You shouldn’t assume that one character is definitive proof.