DJI's airport list is a very patchy effort. If they were trying to properly list airports worldwide they have done very poorly.
They've left thousands out. Looking at their map, they don't know about some of the worlds busiest airports like Dubai, Singapore and Bangkok. They have no airports at all in Africa or the middle east and Australia has no B airports at all.
But for every A airport they have cut out very large circles extending a very long way from the airports.