I see some of the top speedrunners trying to minimize time in the air. For example, in the second room of Ceres station, and in the beginning of Parlor. Why do they do this?

I would assume that as long as you hold the direction after a running jump, the speed you were running at would be preserved, only you're now in the air. Is that not the case?

You might say, "Well, if the top runners do it, then of course," but another reason a speedrunner might minimize airtime is simply due to habit, especially after hundreds or thousands of ledgegrabs and downgrabs.

I'm looking for an exact answer supported by some well-known Super Metroid resource / speedrunner, or actual proof (e.g. via Ram Watch).