https://wccftech.com/the-2020-magic-keyboard-works-just-fine-with-the-2021-m1-ipad-pro-video/

We can finally put this to rest - the 2020 Magic Keyboard works just fine with the 2021 12.9-inch iPad Pro with M1 chip.

A few weeks back we came across a report from iGeneration suggesting that the 2020 Magic Keyboard does not work with the 12.9-inch iPad Pro with M1 at all. The report made it sound like as if we had to throw away our current Magic Keyboard just because the new tablet was 0.5mm thick and buy a newer model from Apple once again.