I know someone that had a retired racing greyhound and a cat, the greyhound was afraid of the cat, lol. It probably comes down to the individuals though, as well as how they are raised, you can't really judge a whole breed the same. For example rough collies are known for being great with other animals and have a low prey drive (the opposite of greyhounds), yet I've heard of some needing to be rehomed because they kept killing chickens and in some cases killing cats. Also it can also depend on the cat too, some are more mellow so the greyhound is less likely to think "prey" just by seeing a cat for the first time, and some are more crazy and zoomy, which will cause the greyhound's prey drive to kick in.
Yes, I know a few sighthound breeders with cats even. It's more an individual dog thing than a breed thing, I have pit bull mixes and have fostered a husky and various terriers and not had a cat aggressive one yet. Now living with a cat and being safe with strange cats outside aren't the same thing, my dogs have lived with cats always but if they see one outside or in someone else's house they want to chase. I also would never just throw a dog into a house with cats without precautions, slow intros, leashed at first, dog crated when I'm gone or unable to supervise until I'm very confident there won't be an issue, cats should have plenty of high spots and a dog free area to escape to.