I would wager that the Forbes editor was just following the required stylebook.
It is now considered proper to use the plural "they/their" to avoid the specific gendered pronoun.
There was no need in this instance to use the plural.
I would appreciate seeing the stylebook notation that so requires.
Are you saying that if a man runs over a cat in the street, the stylebook allows (or requires) the man to be described as "they"?
The headline is illiterate no matter what the excuse; maybe the stylebook is too.