Why is the Smart Controller, which I use with other drones, not yet compatible with the Mini2?
This is very strange !!!
Yet the original remote control is already compatible with the Mavic Air 2 which is compatible with the SC.

it's not a word association or math equation, there are actual technical details involved in the compatibility.  there might even be timing and/or marketing issues as well.

Hello there ToscanaDrone. Thank you for reaching out and for giving out your valued insights with regards to this matter. Currently, the DJI Mavic 2 Series and the DJI Mavic Air 2 are compatible with the DJI Smart Remote Controller. This matter has already been forwarded to our DJI R&D Team for further evaluation.  Kindly please stay tuned to the latest DJI Mini 2 updates by subscribing to DJI official website at www.dji.com or following us on social media ( Facebook: https://www.facebook.com/DJI , Twitter: https://twitter.com/djiglobal , YouTube: https://www.youtube.com/user/djiinnovations ). Thank you for your support and please stay safe always.