It isn't hatred toward Horn. It is immense respect for Downey. Of course, Downey isn't the only guy they lost. They lost their three top guys. That's 47 of their 78 ppg, 6.3 of their 9.9 APG, and over 1/3rd of their rebounding per game. Plus, Downey single-handedly won some games for USC last season. Downey averaged over 30 points in the 6 SEC games USC won last season. In the KY win, he scored 30 points -- the rest of the team score 38 (Raley-Ross, also gone, picked up 17 of those 38). So, two guys who accounted for 47 of USC's 68 points against KY are bye-bye. Downey got 33 against UGA -- rest of team scored 45. 29 against LSU -- rest of the team 38. 18 of those 38 were from the other two seniors.
Muldrow is the only guy USC has returning who has shown he can play SEC basketball at a high level. That doesn't mean the three rising sophomores (Jackson, Galloway, and Spinella) might not turn out to be quality SEC players. They have a big recruiting class coming in with two studs in particular at PG and Forward, but to say USC will be better means that (a) those two newcomers along with the improvement from the returning guys has to be better than Downey and Raley-Ross with where those returning guys were last year; and (b) the rest of the conference has to be worse at a level that makes a difference. I don't see TN, KY, Vandy, or UGA being down from last year at a level that allows USC to catch-up. In fact, with Vandy returning 3-4 guys who have shown they can play at a high level in the SEC, UT returning the same amount and adding a franchise player, and UGA returning two of the best 10 players in the SEC (Thompkins may be the best overall), I don't see USC winning more than 3 SEC East games this season (UGA, Vandy and KY at home, perhaps, but even those last two are iffy).
Has nothing to do with Horn. He'd have to have a season like Pearl's first in Knoxville for USC to have a better season.