Why doesn't Solari play Isco anymore?
Isco doesn't really fit in their current set up. His build up play is far too slow with how Madrid play now. He's also a defensive liability.
To play Isco they'd need him as a 10 in a 4-2-3-1. No way I see them benching one of Kroos, Casemiro or Modric to accommodate him.
I'm even surprised Isco hasn't looked to move on for more playing time. I'm sure he'd do well back in Valencia.