Under normal times one could say this is just policy but at the moment one man and one administration is responsible for most all of this. Even the possible drone FCC ban that congress passed on signed into law by Biden, falls in this...
Without the recorded flight data, DJI or anyone else can't tell what caused your issue.
Did you supply the recorded flight data?
What drone company would you try next?
Trick question ... there's no other company providing drones that are even...
But you also shouldn't go too slow.
There's a "goldilocks" speed in between that will get the best fuel economy.
Sport Mode will burn the battery faster and give less distance.
Fly too slow and you use too much battery power just fighting...
Since the F stop number is the ratio of the lens focal length to the diameter of the front of the lens, two cameras with exactly the same size aperture/opening will have the same "f-stop rating".
Differences in lens materials, the sensor, etc...