DJI forces you to side load their app for their Air Units and Drones. And this is scary. It looks like the rule they violate for the play store is that their app can self modify.
Let that sink in ... Any tension or whatever political bull crap happens and you have a state controlled malware on your device that can do anything it wants with your drone.
Millions of people installed this without really understanding what could be the consequences...
By making it "normal" to install the app via sideloading, there's little Google could do in the event of malicious app behaviour, and the majority of users would not find out about it (at least, not immediately).