My first thought is the character from the Hunger Games. Though I personally don't find the character a bad association, there are people in the fandom who dislike the Career tributes (which Cato is a part of) and see the character as a negative association.
Cato was a spy and messenger from New York during the American Revolution. He used his status as a slave to covertly bring information from Hercules Mulligan (a spy for the Sons of Liberty) to the Continental Army. His information saved George Washington's life twice. Other than his role as an American spy, not much is known about him.
Cato Sundberg is a Norwegian musician and songwriter, best known as the front man of pop group Donkeyboy. Sundberg founded the group in 2005 with, amongst others, his brother Kent. In 2009, the pair were nominated for a Spellemannprisen for their band's debut album, Caught in a Life, in the category of popular music composition.
I think it's a lovely uncommon name that ought to get used more. I remember it was used in The Hunger Games books, but I'd like to hear it more on actual people.
In the Pink Panther films, Cato was the Inspector's assistant. Whenever the Inspector wanted Cato to help him with something, he inevitably bungled it, to great comic effect.
-https://www.nordicnames.de/wiki/Cato
-https://en.m.wiktionary.org/wiki/Cato#Norwegian
-https://en.m.wikipedia.org/wiki/Cato_(given_name)