They are just for the looks as they mess up the axle geometry.
F.e. when parked try to drive backwards with the steering fully to the left or right.
You should hear one tire “slipping”
I haven’t used Insta yet but you can try to relearn the steering sensor values.
I had 0,4 inch spacers (10mm) installed for like 30k miles (50k km) and after removing them the car feels different when driving. The steering feels more crispy but it lacks a bit stability when going straight.