Yes, any sort of demilitarization would make them into a satellite state, crushable at will.

They can possibly agree to territorial losses (though after all the bloodshed and murder I consider even that unlikely - not just that, but the West does not want Putin to gain anything from this war, so it will support Ukraine until victory, however long it takes), but not to any kind of hollowing out of their army. That would be a prolonged national suicide.