Bottomline is that the iPad mini 5 and iPad Air 2020 unlock in a similar way, but there is a difference. With the iPad mini 5 you can bypass the Start screen, or whatever it is called, by using a single long depress on the Home button. If you want the iPad mini 5 to go to the Start screen, quickly depress and release the Power button. The iPad Air 2020 doesn’t have the capability to bypass the Start screen. The first action of depressing the Top button activates the Start screen and gives you the option to unlock the device by gently touching the Top button so it can read your finger print to validate you are allowed to unlock the device. I can see a benefit in that, but I doubt I will ever take advantage of just displaying the Start screen on either of my iPads.
I would much prefer the iPad Air 2020 used FaceID like my iPhone XR and the iPad Pro models. But that would mean there would have been even less temptation to fork over another $200 for an iPad Pro 11” model.
ETA: BTW, I seem to have developed a smooth way of getting the iPad Air 2020 to unlock without noticeably displaying the Start screen. It takes a lot of practice, the right touch, and a lot of luck! I’m pretty sure the Start screen does display for a few microseconds, but it is so short that I have to really concentrate to notice it. I don’t always get this technique to work, but the more I use it the more it becomes muscle memory. I’m almost to the point of not thinking about. When I do think about it, I usually have it fail to work.