Are the lenses those manufacturers are releasing in the RF mount also available in other mounts? Do the lenses for other mounts have lens based image stabilization? How much does lens stabilization actually help with wide and standard focal lengths? My 28-70/2 has 8 stops with just IBIS.
Having said that, it does does leave those without IBIS bodies out in the cold… Which is exactly where they don’t want to be, shivering and holding a non-stabilized rig.