Yes, I tried it just now. I've tried removing the keyboard and pairing ut using a lightning-to-USBC cable and also pairing it using Bluetooth. Even so it disconnects from my computer. The keyboard is also charged 100%. I also tried removing the keyboard, cold-restarting the Macbook, logging into MacOS using the Macbook keyboard, and then re-pairing the keyboard. But it disconnects at some point later still.
I've tried to find some sort of procedure that always trigger this. Sometimes it seems to be linked to TouchID. I can lock my screen (Control+Command+Q) and then use TouchID on the Magic keyboard to unlock and then the keyboard no longer responds. After this I either have to disconnect and reconnect the keyboard in Bluetooth preferences or switch the keyboard off and on again.
Also, TouchID takes two-three seconds when using the sensor on the Magic keyboard, while it takes less than a second when using the TouchID sensor on the Macbook.
I also see that if I connect the cable to the keyboard, it respons without any problems and the TouchID is just as snappy as the one on the Macbook keyboard.