In a recently interview with Canon UK’s product intelligence consultant David Parry by DCW, he explained that why Canon EOS R (B&H Photo Video/Amazon/Adorama/Focus Camera) doesn’t have IBIS like other mirrorless cameras.
According David Parry, Canon think that in-lens IS is the optimum system for image stabilisation, because different lenses has different types of IS. And Canon is also looking at IBIS.