Yes. Federer for example is one of the greatest players of all time, maybe GOAT , but he is very bad person.
Fed is one of the very greatest of all time, for sure. I am sure he is not a bad person, but seems to be arrogant and a sore loser. Most of his arrogance, IMO, is due to his great success during the weak years of 03-07. Fed-Nadal, Novak-Fed, Novak-Rafa have been great rivalries. Murray is just a shde below the top three, usually giving them very tough matches. I totally agree with Agassi's assessment of his VS Novak's abilities. The same is basically true of Sampras VS Federer's abilities. All of them are great players, to be enjoyed and admired, not to be trashed by nasty nobodys here.