Horton Plaza is on the verge of becoming condos/apartments IIRC. No surprise Macy's is closing; to be honest, I'm surprised to learn that it's still open!
I loved Horton Plaza. On a personal level it's where I met Cleveland Indians GOAT, Hall of Fame pitcher Bob Feller: odd, considering I'm originally from the Cleveland area, spent the first 22 years of my life in Central OH, but ended up meeting one of my all-time favorite baseball players in San Diego! He was doing signings in a sports memorabilia place in Horton Plaza, and my wife and I were there with our son (then a toddler, now an 18 year old) and virtually no one else. I got to chat quite a bit about old-time Cleveland baseball and some of their great players that were teammates of Feller (Feller was the Ace pitcher on Cleveland last World Series Champion team in 1948; and Feller was teammates with fellow pitcher Larry Doby, the first black player in the American League who followed Jackie Robinson less than three months after Jackie made his debut).
But the gluttony of shopping malls from the 1990's-2010ish is over