> The evolution a system undergoes when you measure it in the Copenhagen interpretation does not follow the schrodinger equation

Do you have experimental evidence for that claim? The "cat in a box experiment in a box" thought experiment suggests that it does.

They're talking about what the Copenhagen interpretation predicts, not what actually happens. It's a mathematical question, not an experimental one.

Solutions to the Schrodinger equation all take the form `Psi(t) = U(t)Psi(0)` for some unitary operator `U`. "Collapse" applies a projection operator, which is nonunitary.