This isn't automatically true. Depends a great deal on the size and traffic at the airport.
Back in the day when I was an active Private Pilot, I visited many small airports where I was the only plane to land and later take off the entire day...
I thought the December 23 deadline works as follows:
DJI will be placed on the Covered Entity list if a national security review is not conducted or it fails said review. This is from the 2025 NDAA.
Once added to this list, the FCC will not...
What props is you brother using? It looks like the spark can achieve a 1.9 thrust ratio with standard props. This would certainly limit your angle of flight. Ballparking,around 45deg before losing altitude