The new 1Dx III wil just be a little upgrade from the mark II.
A little better ISO performance, a little more K video, a little more resolution, a little faster, a little more accurate.
No IBIS, no Mirrorless, just same old same old, just a little upgrade. Of course with a lot of spin/marketing online on vague terms as deep learning AF blablabla.
If we are lucky we get eye AF in mirror up modus, but I'm affraid even that is not the case.
2020 is the time Canon must show what they can put up against the supersharp and accurate (eye AF) sony mirrorless cameras, or the only thing we see in 2021 from Canon is a new printer.