Terminal Velocity Not In The Quran
The Quran doesn't talk about terminal velocity at all.
During a free-fall terminal velocity is reached a few seconds after the drop.
Based on wind resistance, for example, the terminal speed of a skydiver in a belly-to-earth (i.e., face down) free fall position is about 195 km/h (120 mph; 54 m/s). This speed is the asymptotic limiting value of the speed, and the forces acting on the body balance each other more and more closely as the terminal speed is approached. In this example, a speed of 50% of terminal speed is reached after only about 3 seconds, while it takes 8 seconds to reach 90%, 15 seconds to reach 99% and so on. Wikipedia, Terminal Velocity, 2019.
Skydivers have high terminal speed however there are birds that can easily overtake any skydiver.
The Peregrine Falcon reaches terminal speeds of 389 km/hr and the Golden Eagle reaches terminal speeds of 240 - 320 km/hr. So these two birds can easily overtake any skydiver in a free-fall. They also turned-out to be raptors (flesh eating birds). This was only recently, however 1400 years ago this was portrayed in the Quran:
[Quran 22:31] Being true to Allah, without associating anything with Him. Whoever associates anything with Allah it is as though he has fallen from the sky, and was snatched by the birds, or was taken down by the wind to a deep place.
"Was snatched by the birds" these birds are attacking humans means they are flesh eating raptors. But to catch humans in mid-air they have to dive faster than the skydiver. Today we know that there are two raptors that can easily overtake any skydiver.
How could an illiterate man who lived 1400 years ago have known that some raptors are faster than skydivers?
Being true to Allah, without associating anything with Him. Whoever associates anything with Allah it is as though he has fallen from the sky, and was snatched by the birds, or was taken down by the wind to a deep place.
The verse says nothing about terminal velocity. And the part about the birds is preceded by "as though".
You use as if and as though when you are giving a possible explanation for something or saying that something appears to be the case when it is not.
So the Quran doesn't even claim that it is the case that birds can do it. It only uses this imagery as a parable. So the miracle claim is completely baseless.
Birds are skydivers?
The apologetic claim contains "to catch humans in mid-air they [the birds] have to dive faster than the skydiver". Birds are not skydivers. They can fly. And they don't have to be faster than a skydiver to catch him. Nothing in the verse says that the birds and the human start at the same height. So if the birds are lower, they can do the snatch even though they are slower.
Did birds ever catch a human skydiver?
There have been accidents of bird-human collision but their is no evidence of a bird who caught a skydiver. Muslims are saying that birds catching humans in mid-air was not known to Muhammad and therefore the Quran is made by God because only now we have found that birds can catch humans. But when did a bird catch a human in mid-air? This catch needs to happen first. If it does not happen, the argument of Muslims does not make sense.