iPad Air compatibility with current Apple TV or Apple TV 4K

AirPlay is supported across all devices that can use AirPlay. 2013 or 2019, it is all good.

AirPlay system requirements - Apple Support

Devices you can stream from: iPhone, iPad, or iPod touch (iOS 4.2.1 or later), Mac, iTunes on Mac or PC, Apple TV (4th generation or later)

Devices you can stream to: Apple TV (2nd generation or later), selected speakers

Air Play Screen Mirroring has different system requirements than basic AirPlay, but any 2012 or later equipment should be fine.

Not all apps have AirPlay enabled (i.e. block it). Some apps shift automatically from mirroring to ‘basic’ AirPlay.

yes it should, if you mean support airplay mirror, the appletv can't access the media lib of your ipad on it's own though it can only access computers shared libs

How to AirPlay video and mirror your device's screen to Apple TV - Apple Support

If you can't use AirPlay or mirror your device's screen - Apple Support

My ipad doesnt have airplay how do i acti… - Apple Community