I have my Air 5 and it is working flawlessly. It was an upgrade from the forcibly updated 9.7-inch iPad Pro, and I saw it as a huge upgrade. I primarily value performance and battery life, and it delivered on both when compared to my significantly affected - but not destroyed - 9.7-inch which runs iOS 12.
Now, the Air runs and will run iPadOS 15, so for compatibility reasons I got a little companion, the 11th-gen iPad. Purely for software reasons, as there’s absolutely no problem with the Air 5. Everything runs as it should, but that’s just me being cautious. Software compatibility will eventually be an issue for some things and I wanted to have an option that’s not updating and destroying the Air 5.